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Download file "apenvirolaws.pdf"
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Climate change

Download file "Climate change.pdf"

Climate change

In any crisis, the following steps might help you survive, thrive, or perhaps impact change:

  1. What is the crisis? What words define it? What is the lexicon?
  2. Why should I care? How does this impact me? How will it impact my kids/grandkids?
  3. What are the mechanisms of cause and effect?
  4. What impact timeline can I expect?
  5. What can I do: directly, locally, globally?
  6. How can my understanding of the situation help me impact the situation?

“We are on the precipice of Hell”

-Frontline video HEAT

“Climate change is the biggest business opportunity in the history of Mankind”

-Tito Jankoski, climate change activist, carbon sequestration pioneer, HPA ’05

“Greenhouse”-why? how does a normal greenhouse work? what parts relate to which physical systems?

Demo: car dashboard is dark, absorbs visible radiation passing through the car windshield, re-radiates at lower frequency/longer waves (heat), which is trapped by the glass windshield.

glass=greenhouse gases (CO2, methane, water vapor)

Is this always bad? See diagram:

Earth would be 0°C without any greenhouse effect

These gases have different impact and lifespans:


Where have I seen these before? You might not, but your parents certainly did, about 30 years ago, when the ozone layer was being destroyed by refrigerants (gases we created called “Freons” we used in refrigerators, freezers and air conditioners)

Without the ozone layer, everyone on the planet would suffer from UV radiation, causing skin cancers, plants would die, so would some life in the oceans. This was serious, causing an “ozone hole” over Antarctica:


Here’s how we know we can act globally to avoid disaster:

In 1997, most of the countries of the world met in Montreal Canada to create the Montreal Protocol, banning these CFC’s (chlorinated fluorocarbons) like Freon.

Here’s how we know it worked:


Note the bottom graph. What do you see? When did things change?

Here’s what the trend is for greenhouse gases: (2011 version on the link below)

http://physics.hpa.edu/physics/apenvsci/_pdf/aggi_2011.fig4.png

2017 version:



NASA simulation:

https://climate.nasa.gov/interactives/climate-time-machine

NASA Eyes simulation:

https://eyes.jpl.nasa.gov/eyes-on-the-earth.html

Where is this stuff coming from?


Ok, what gases are naturally sourced:

Volcanic eruptions (complex, as the ash can actually block sunlight, temporarily cooling the planet-see Mt. Pinatubo)

Decomposition/digestion (methane from termites and cow gas, or the truly horrific possibility of melting permafrost)

Denitrification (wet soils, wetlands where NO3 turns into N2O)

Evaporation/evapotranspiration (water vapor)

Human (anthropogenic) causes:

Fossil fuels use (coal, then oil then natural gas)

Deforestation

Agriculture (nitrogen fertilizers)

Landfills (methane again)



Two graphs are important to you:

Here is the pattern of CO2 measured at Mauna Loa since 1958, the famous “Keeling curve”


Here is the historical record, from ice cores and other data:

Note the date...
Where is this coming from, by nation?


Why? US burns fossil fuels like maniacs, China is opening two coal fired power plants EACH WEEK, India is making concrete by heating CaCO3, releasing CO2 to make CaO (“Portland cement”)

So what?

Global warming will change the global temperature, impacting weather, sea levels, severe storms, glaciers, water and food supplies

High CO2 causes ocean acidification, killing corals, and impacting all life in the ocean, a major absorber of CO2 and source of food

Finally, high CO2 levels make us stupid. Anything over 800 ppm has been demonstrated to impact learning, memory and complex thought. There is no escaping this, much like the ozone crisis of the 1980’s

Here’s how warm it is getting:


How do we know CO2 and temp are related?

Check this out:



Here’s what this will look like when you are having grandchildren:

The first picture is 2020-2029, the right side is 2100, when you are in your 90’s:


These assume a constant rate, which is unlikely if the permafrost begins to melt, releasing more methane, and the polar ice caps melt, changing the albedo (remember Albus Dumbledore).

This is an example of a positive feedback loop.

n.b. most folks believe that ocean levels will rise from the melting ice caps and glaciers. This is only a small impact, the greatest impact is that water expands when it warms, so ALL of the water in the ocean is expanding at once, and the ocean is several miles deep around the world-think of that!


https://fitzlab.shinyapps.io/cityapp/

What can we do?

The IPCC (intergovernmental panel on climate change) inspired the 1997 Kyoto Protocols, which the US has not followed.

Here’s what they say:

So, back to our questions:

  1. What is the crisis? What words define it? What is the lexicon?
  2. Why should I care? How does this impact me? How will it impact my kids/grandkids?
  3. What are the mechanisms of cause and effect?
  4. What impact timeline can I expect?
  5. What can I do: directly, locally, globally?
  6. How can my understanding of the situation help me impact the situation?

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Heat Frontline video-climate change

Heat Frontline video

http://physics.hpa.edu/physics/apenvsci/videos/heat/Heat.m4v
(starts at minute 3:00)

Some notes:
You might recognize some of the clips from this film in our other videos like the e2 videos, like the coal vs. nuclear video.
This video was first produced and aired in 2008, so some references to presidential campaigns may take you into recent US history.
This is a big assignment, so take your time, and we'll break the due dates into two parts: questions 1-30 and 31-60.
Let me know if you have any questions
aloha
b

1 What river is China planning to divert that will cause conflict with India?

Brahmaputra river

2 Why did Brashears go back to that specific site to take the photo, and what did he see? What possible explanations are there for this? Take both sides of the climate crisis argument in your answer.

Brashears went back to the specific site to take the photo to see the changes by comparing it to the past. It was obvious that the amount of ice of glaciers had decreased. This is because of the global warming and increase of population.

3 What was so surprising in the 1958 movie? Was this common knowledge? How can you tell?

awareness of the issue long ago...

4 How did the cheapness of energy influence public opinion?

no need to conserve

5 Is the climate crisis an energy issue, a tree issue, an albedo issue, or a permafrost issue?

all of these

6 What happened at Kyoto? What was the most embarrassing part? Why did the US behave so?

Bush admin was tied to oil companies (he owned one, so did the VP, Dick Cheney, and all of their buds, even the Saudis)

7 Why would China's growth outweigh any changes the US might make to change carbon emissions?

US: 350 Million, China: 1.3 BILLION or 1300 million. Apples and oranges.

8 What is Geely? Where? What model is their biggest seller? Is this scary? Why? What did their director say?

private car company in china, builds huge cars, no need to conserve as money is loose there. this is changing: China wants to produce 1 million electric vehicles next year

9 How many coal fired power plants does China create every week?

Two. Each one will produce CO2 for 40+ years.

10 Dr. Ling Wen says 30% growth over 5 years. What is the doubling rate for this? (recall the rule of 70). Why is his line "if we can" so scary? What are his responsibilities, in what order?


11 years, only to the shareholders...

11 In what year will India's population exceed that of China? Why?

While you are in college:





12 What is the third largest contributor to greenhouse gases? Where?

Concrete production, in India: CaCO3 ->CO2 and CaO (aka portland cement)

13 What reduction in CO2 did the Indian guy say they could do by 2050? What is the growth rate? What did Sunita Narain say about this? Why is this not sustainable?

10%

14 What did Pachauri say? What are his reasons?

150 years of industrial pollution, therefore our responsibility

15 What did the US negotiators say? Why is this unfair? What did China say?

not our problem-this may have changed a bit since the video was released

16 Google Senator Inhofe, and find out why he is a global warming skeptic. Where does his money come from?

coal

16 This video was filmed in 2008. What was the position of each candidate?

clean coal, to keep jobs in the coal states of WVA, Kentucky, etc.

17 What did Jeffrey Sachs say?

we ignored the problem

18 How many tons of coal are mined in the powder river basin each day?

1 million. each ton of coal produces 2.8 tons of CO2, so 2.8 million tons of CO2 per day

19 The director of the West Virginia power plant (Charlie Powell) says: "we produce 1300 megawatts of power every hour". It is clear he does not know as much about electricity as you do. What is wrong with his statement?

megawatts already has time in it: 1 Watt is 1 Joule/second, so it is like saying "miles per hour per hour"

20 How many pounds of Coal power your TV for one hour? What percentage of power in the US comes from Coal?

0.2 pound per hour, 52%

21 Analyze the term "clean coal" from both sides of the argument. What are the motives of each side and why?

It is a myth, devised by the coal industry to blunt criticism of their role in global warming

22 Senators Byrd and McConnell represent which states? What is their bias?

W.VA and Kentucky, both coal states

23 What is IGCC? Where is it located? Has it been tested? Where would they inject the ground? Why is this dangerous? Are we "carbon capture ready"? Where would this be tested first, and why is it problematic? If pipelines were used, why would these be dangerous?


Integrated gas combined cycle, basically gasifying coal to produce power, then storing the CO2 someplace. Where is an issue: nobody wants to die in a cloud of CO2

24 How many tons of CO2 does the US emit every day?

Actually closer to 3: 2.8 million tons per day (see above)

25 The US is called the "Saudi Arabia of Coal". Why?


Lots and lots of coal

26 What is the second largest emitter of greenhouse gases? Now list the top three in order.

power plants

cement

cars and trucks

27 What are CAFE standards, and what does it stand for? What happened in the last few years to the CAFE standards? When were they created, and track the mpg numbers since then. How did auto manufacturers get around the CAFE standards since the Ford Explorer came out?

combined average fuel economy

27 What is John Dingell's motive? Why? Where is he from? Why did he block seat belts? Is his responsibility only to his 800,000 citizens or to the country, or the planet as a whole?

He is from Detroit, which used to make cars. He blocked seat belts for years saying they would add too much money to cars (about 60$ per car). He died last month.

28 What MPG is "the terminator" seeking for California? By when? Jerry Brown is next in the video. What is his job now?

42.5 MPG. Jerry Brown was governor of CA for years, when I was in college (his name is on my diploma from Berkeley), then again when this video was shot. He is retiring this year.

29 In the 1970's all cars in the US came in two flavors: "49 state" or "CA". Why?

California had higher efficiency and pollution standards, stricter to control air pollution and lead levels which were impacting kids' brains among other things.

30 What pressure was put on the EPA in December 2007? Who was in office then?

Don't let CA have stricter rules for pollution. George Bush (oil guy again)

31 What is the clean air act?

32 Who was the EPA administrator during the Bush administration? What did he do? What do you think about his actions?

33 What was the target of the CA emissions standards?

34 What is Hibernia owned by Exxon? How much oil did it pump since coming into operation? At 80 million bbl/day, how many days of global oil supply did it provide?

35 How did the Exxon lady defend their lack of investment in renewable resources?

36 Dan Kammen says what? Where does he work?

37 How much did Exxon make in the year of the movie? How much did they invest in renewable energy? Explain.

38 It has been said that if you drive a Prius hybrid with fuel from the tar sand of Canada, it's the equivalent of driving a Hummer. Why?

39 During the 2008 video, they state that oil is at $90/bbl. What is it today? (bbl means barrel)

40 The car companies were working on a diesel-electric hybrid: what happened and why?

41 What did Toyota build, and why? How long is their advantage now?

42 Do you believe the lady from GM? Explain.

43 What happened to the Chevy Volt in the Photo Shoot?

44 Is corn ethanol really a green solution? Who is pushing corn ethanol and why?

45 Why does Dan Kammen say corn is not a good biofuel?

46 Explain the three sources of bio-ethanol: corn, cellulosic and sugar cane. Brazil produces which of these?

47 How does Amy's statement about small interests resonate with Senator Dingell's actions earlier in the film?

48 Compare renewable energy in Germany to the US.

49 How does the smart grid fit into the renewable energy solution?

50 T. Boone Pickens sold his oil investments and moved into wind farms in Texas. Check into this on wikipedia to see how he's doing now (2019).

51 About 150,000 megawatts of power is what Pickens plans on installing, which would be worth how much per year? 24 hours per day, 365 days per year, sell the power for $0.10 per kWh. 131.4 billion dollars per year? If his ROI is 7 years, and the turbines last 17 years, how much money will his company make overall?

52 Why is nuclear energy getting a fresh look?

53 Who became president after this video?

54 What is the difference between Navy nuclear power plants and commercial industrial power plants?

55 How is nuclear waste storage involved in this problem?

56 Explain cap and trade, and the plus and minus for this proposal.

57 How has the flood of natural gas from Fracking impacted the coal industry?

58. Why is natural gas better than coal for this? (think of the types of power plants that use each)

59. Coal has pollution impacts that natural gas does not. Explain.

60 What was the most compelling part of this video for you? How old will you be in 2030? 2050?

http://physics.hpa.edu/physics/apenvsci/videos/heat/Heat.m4v

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APES notes HPA 2030 plan

apes notes: HPA 2030

budget $50M

international, boarding, 9-12 (13-16?), 600 students

240 acres (24 ha)

sustainable

“greenest school in the world”


Things to include:

energy: microgrid? co-op? PV, PSH, solar thermal, batteries?

water: harvesting, storage, conservation

food: what can we grow, how? CSA?

waste: within state rules, solid waste, recycling

housing: 300 students, international

transportation: intracampus, off campus

security/emergency profile

maintenance: buildings, lawns, pool

athletics: pool, gym, tennis courts, fields, horsies

library/information center(s)

study locations

chapel/meditation spaces

recreation centers: student union, nap-pods

classrooms: flexible, effective learning spaces

meeting spaces: students, larger groups

theatrical/presentation spaces

food service: central or distributed?

administration spaces


other considerations:

community outreach

research projects

hosting groups

college collaboration/hosting

mindfulness

conference center

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Solar radiation lab

Outline:
We will calculate the efficiency of two solar energy harvesting systems: the PPA photovoltaic array above the elab, and the solar thermal panels above the bathrooms at Perry-Fiske (neé "Anna's").

Steps: PV array
  1. Measure the dimension in meters of one panel of the PPA array above the elab
  2. Count the total number of panels
  3. On elab2.hpa.edu, measure both the energy harvested from the array around noon or whenever you took your data, and the solar radiation here at the same time (look under "Telemetry"->"HPA Energy")
  4. Alternate data source: http://elab4.hpa.edu/cgi-bin/EMCcgi?, look under "dashboards" then "other dashboards" for the one called "HPA campus energy". You can also use "monitor" to graph solar and radiation data.
  5. Multiply the solar radiation (in W/m2) by the area (in m2) to get total Watts of solar energy falling on the panels.
  6. Divide the harvested energy (in Watts) by the radiation (in Watts) to get % efficiency (recall the number should be less than 1.00 or 100%)
  7. How many kWh per day would this array provide at 5.5 solar hours per day?
  8. How many $ is this, assuming $0.40 per kWh?
  9. HPA has the option to purchase the PPA array in 2 years for about $150K. What would be the TCO and ROI for this array if it lasts another 15 years?
  10. How big (panels or m2) would the array have to be if it were 95% efficient (like solar thermal) gathering the same power?

Steps: Solar thermal array, Perry Fiske
  1. Count the number of panels on the bathrooms at Perry-Fiske (both buildings)
  2. If each panel is 2 meters wide and 3 meters tall, what is the total area of one panel?
  3. What is the total area of all of the panels?
  4. If these panels are 95% efficient, using the same solar insolation (radiation) numbers from above, how many Watts of power would you expect from this array?
  5. How many kWh would this provide, if it ran for 5.5 hours per day?
  6. How many $ is this, assuming $0.40 per kWh?
  7. If this array cost $2000 per panel, what would be the TCO for one panel?
  8. What would be the ROI if it worked for 20 years?
  9. If propane produces 23 kWh per gallon, how many gallons of propane have we avoided in 20 years?
  10. If 12 pounds of CO2 are released for every gallon of propane, how many pounds of CO2 did we avoid in 20 years?
  11. How could drones be used on our campus to make certain our solar thermal panels are working properly? (hint: think of the thermal camera we tested in class)
  12. Our pool has a very low efficiency solar thermal system on the roof of the locker rooms. How are these leaks costing the campus money?
Green New Deal: carbon neutral by 2030
  1. How is this like the New Deal in the Roosevelt era?
  2. How is this like the moonshot in 1960?
  3. What would be different about our country if we were net carbon neutral in 2030?
  4. What impact would this have on climate change, directly and indirectly?
  5. People will be asking you about this, since you know so much about energy. What would you tell them?

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Power Factor power rangers!

Power Factor lab

What to measure:

Ohms (using the yellow meter set to Ω)

Volts (these are measured with the little kill-a-Watt meters)

Amps

Watts

Power Factor

Predicted Power from P = VxI

Actual Power

Ohmic (heating) or not?

Where to find stuff to measure:

Classroom:

Laptop chargers

computer

TV

Hall way:

Vacuum cleaner 1 (old style)

Vacuum cleaner 2 (Dyson)

Main hall:

Hot water heaters

stereo

coffee maker

coffee grinder

Robotics lab:

Coffee grinder

Coffee maker

toaster oven

desk lamp

Conference room:

TV (east side)

stereo

Computer

other TV (west side)

other stereo




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e2: the art and science of Renzo Piano

e2-design 3.4 Renzo Piano

http://physics.hpa.edu/physics/apenvsci/videos/e2_videos/e2%20design%203/4%20the%20art%20and%20science%20of%20renzo%20piano.m4v

Brad Pitt

  1. Have you ever visited the California Academy of Sciences (CAS)?
  2. What “story” is Piano telling?
  3. What environmental ethic went into the energy lab?
  4. If the earthquake of 1989 had not happened, do you think this would have been built?
  5. What is our mission here? What was our statement?
  6. How did the creative process differ from “normal” design processes? Why is this important?
  7. How is the term "transparency" used here? Do you see it here as well?
  8. How does this project combine honesty and green building?
  9. What do they mean by “biomorphic”?
  10. Look up biophilic building design. How is this relevant?
  11. This project combines research and education. Why might this be familiar to you?
  12. What two factors enable native species on the roof to resist invasive species?
  13. What "what if" would you imagine?
  14. In the frame with Sutro radio tower (look this up) in the background, what visual flow do you see? (15:21)
  15. We will soon learn about runoff and something called “water transit time”. How does the roof increase water transit time?
  16. Note the square white sound panels like the student union-how do these work?
  17. Piano describes ecology as a “moral duty”. Why?
  18. On the south lanai of the elab, there are special solar PV panels. Where else have you seen these? Why?
  19. Darwin traveled around the world collecting specimens that informed society about diversity and evolution. How is this similar at CAS, and why is it important today?
  20. How is this project empowering? To whom?

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Smart buildings

The energy lab is a model of sustainable building, meeting both the LEED for schools Platinum criteria and the elusive Living Building Challenge, the first school building in the world to do so.
The US green building council established the LEED specification to promote leadership in energy and environmental design (LEED), but has no post-occupancy monitoring.

LEED for Education scorecard for Energy Lab:

Download file "01352d LEED for Schools Checklist.pdf"

We created the TCM (telemetry control and monitoring) system you know as elab2hpa.edu, and later the EMC systems to monitor all of the metrics specified in the LBC evaluation. These criteria formed some of the "petals" of the LBC, which is pass/fail.
The monitoring system had to gather data on water, energy and environment every few minutes for a year. If we interrupted the data gathering, we had to start over.
We were then audited and later certified in 2011, one year after the building opened for students.
Some of the criteria of the LBC include self sufficiency in energy, water and waste. Nothing in the building can be toxic in either production, use or disposal. We also had to source our materials based on density, meaning our building had less impact on the planet through transportation of building materials than any other building.
Look around the elab for the following features:
  • passive ventilation
  • passive illumination
  • double glazed windows
  • visibility to the outside from every space
  • large thermal mass
  • heat pump for heating
  • thermionic heating and cooling
  • water catchment and treatment
  • onsite waste treatment
  • solar PV
  • solar thermal energy
  • wind energy
  • no toxic materials
  • building automation system to minimize vampire loads
  • locally sourced materials based on density
  • FSC certified lumber
  • LED lighting
  • energy storage systems
  • low sound levels
  • adequate lighting levels
  • No VOCs present
  • Adequate ventilation (low CO2, adequate ACH)
Questions:
  1. If this building cost 3.7M$ to build, and has 6550 sq. ft. of area, what is the cost per square foot?
  2. How does this compare to other buildings in Hawaii in general, and resort homes in particular?
  3. What advantages to the systems above have from a cost standpoint?
  4. What other advantages to the systems above provide?
  5. Why is this so important for an educational facility?
  6. Look up LEED for Schools. What are the major guidelines we had to follow?
  7. Look up the Living Building Challenge. What are the 7 major petals?
  8. Why are these different from LEED?
  9. If you were designing a new school building, what would you include?
  10. Our next project will be to design a new school. What lessons would you bring into this design process?

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Net zero energy

Net zero energy neutrality:

HPA is in effect our own "micro-grid" meaning all energy we use and capture is measured by one HELCO electrical meter near the lower gate to the upper campus. This meter measures kWh, and through some calculations, we can determine our rate of energy use in kiloWatts through the day. As you can see from our graphs, we are energy neutral, or generating more than we are using when the HELCO meter reads zero:

In the graph above, we were net zero with the electric utility (HELCO) at around 9 AM, then mostly until about 1 PM, which is unusual for our campus, since this was a cloudy day. We are usually energy neutral from around 8 AM until 4 PM each sunny day. Net zero means that the total of out and in equal zero.

We have three ways we can claim net zero energy neutrality:

  1. Net energy neutral: We export the same amount of energy around noon that we use overnight, so as far as the HELCO grid is concerned, we have a net zero energy profile. We still pay for what we use at night, though)
  2. Net money neutral: We capture any excess energy during the noon hours when the HELCO meter would be spinning backwards, and use this at night from our batteries or other storage). If we were allowed to sell power to the grid, this would also work.
  3. Net carbon neutral: We measure all carbon used on campus, including transportation, heating and other carbon impacts and offset with energy produced via solar thermal, PV, wind or other means (not nuclear, don’t worry). This is the most current global metric used, and relates well to our sustainability misssion.

Each has certain PR and moral aspects, depending on the goals of the organization. Since our business is creating change agents to solve sustainability issues in the future, each of these is important.

Questions:

  1. If we were to attempt #1 above, how could we offset the propane, diesel and gasoline used in other parts of the campus?
  2. What are these other uses, in other words, what are all of the energy uses on campus?
  3. If we were to try #2 in the Waimea community, who could our "customers" be?
  4. How much would #2 cost us if we used lead acid batteries?
  5. Lithium batteries?
  6. Pumped storage hydro? (you might have to do some research on this using the energy primer wiki)
  7. If we were to become carbon neutral, how could we offset the fossil fuels we use on campus?
  8. Would we first have to become one of the other options?

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Energy Storage

Energy Storage:

Batteries for large scale systems are usually either lead acid batteries dating back to around 1800, or lithium batteries from this century:

~1800 lead acid batteries

lead and sulfuric acid

environmentally nasty

3 year lifespan

shorter if used more

only 40% of capacity is usable

slow discharge and recharge

about $300 for each kWh stored


Example: our overnight campus use is about 100 kW for 20 hours or 2000 kWh (or 2 mWh). At $300/kWh this would cost us $600,000 and would last 3-5 years at max capacity, but in actuality it would be 2.5 times this because these batteries cannot be discharged all the way, so $1.5M.


~2010 lithium batteries (LiPO, Lithium iron phosphate, etc.)

Used in Prius, Leaf and other cars

lightweight

fast discharge and recharge (good for regenerative braking in cars)

20 year lifespan at 80% capacity

greener

expensive ($1300 per kWh)

Tesla's Power Wall is one example, so is the blue box in the student union and IT office. Kauai island is using these to move that island to complete energy neutrality in the next few years.


The same example above costs more, last longer, and requires fewer batteries. It also discharges faster to maintain our microgrid, and recharges faster when used as backup power for the IT building, protecting our computers from multiple outages we face with HELCO.


Pumped storage hydro:

Water tanks low on campus have a pump and a generator. When we have extra energy, we pump this water uphill to a similar tank where it is stored for use later on. When needed, the system activates the generator, which provides power for the campus. This is green, cheap, renewable, lasts 50 years or more and can be safely integrated into other water systems (e.g. fire suppression) as needed.

Walkaround:

Check out the lead acid battery bank in the elab.

Check out the lithium storage system in the student union.

Questions:

  1. The storage system in the elab provides 48V of voltage for a max of 60 AH. What is the power of 48V x 60A?
  2. If our system can provide this power for one hour, how many kWh is this?
  3. At $0.40, how much would this energy cost?
  4. If our elab critical systems depended on this, and used 1000W, how many hours could this system last?
  5. Each 6V battery costs $120 and lasts for 2 years. There are 8 batteries. What is the cost in $/kWh stored per year?
  6. The lithium batteries in the student union store 11 kWh of energy and costs $13,000 but lasts for 25 years. What is the cost in $/kWh stored per year?
  7. The lithium batteries also charge much faster than the lead acid batteries. Why is this an advantage?
  8. Why did we replace the lead acid backup batteries in the IT offices with lithium batteries?
  9. The old IT backup battery system cost $4000 per year and lasted only 4 years at most. What was the cost per kWh per year if it was half of the lithum 11 kWh capacity?

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photovoltaic (PV) Energy

PV (photovoltaic): light to DC electrical energy

If solar thermal captures solar radiation as heat, PV systems convert this radiation into electrical flow in one direction (direct current, or DC, like batteries). This is convenient for battery storage, but to be used in most homes and businesses, AC (alternating current, 60 Hz) is needed. Inverters are electronic devices that turn DC from PV and/or batteries into AC for use.

Since HPA is on one meter with HELCO, we are essentially a “micro-grid” meaning any electrical energy harvested from PV (or released from batteries) goes to slow down or reverse the HELCO meter. Since we do not presently get any credit for energy out, we want to make certain we can store any excess energy on campus for our night time use.

Since the sun is brightest at noon, PV engineers use an estimation of a PV array output called “solar hours”, meaning the equivalent amount of energy harvested if noon lasted that many hours. This is like making a camel hump curve into a rectangle, adding the edges to the top.

For example, our PPA (purchase power agreement) array behind the elab produces about 100 kW maximum. This is true at noon, but less so either side of noon, so we use “solar hours” to estimate energy harvest each day. For us, this is about 5.5 solar hours, depending on season:

100 kW x 5.5 solar hours = 550 kWh or about $200 saved each day.

Click for full-size image



PPA arrangements usually charge us a fraction (about $0.20 per kWh) of the HELCO cost, but we have to pay for what it produces, not what it uses. If we are pushing energy out the door to HELCO using the PPA array, we are in effect paying to give this energy away, which happens during vacations (summer, winter, spring).

Net zero energy is when we have effectively stopped the HELCO meter, meaning we are producing exactly how much we are using.

We hope to harvest enough to reach net zero around 10AM each day until about 2 PM each afternoon. The extra energy during that time we hope to capture using battery and other storage systems (pumped storage hydro, hot water activation, etc.)


Questions:

  1. Using the elab2.hpa.edu system, calculate the power harvested at the same time you measure the solar radiation for the PPA array above the elab.
  2. Measure the area of one solar panel in the PPA array and count the number of panels to get total area.
  3. Use the solar radiation in W/m2 to calculate the ideal power from the array
  4. Compare this with the actual power harvested from the array. What is the % efficiency?
  5. Using the graph above, count the squares to find the total energy for a day.
  6. If the total installed power is 210 kW, how many solar hours did we have on January 20?

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solar thermal energy

Solar thermal:

Goal: Turn solar radiation into hot water

Active systems: Sun—>solar panel—>pump—>tank—> users

Passive systems: Sun —>solar panel/tank —> users (no pump needed, uses convection)

HPA systems are of two types:

Carter dorm has the active system, while Perry-Fiske and cafeteria have passive Solahart systems

Propane is used to finish these systems, making sure that users always have hot water at about 120°F. These are propane "flash" heaters, making sure that any water going to the showers/sinks/washers is always at 130°F. You can see these behind each bathroom if you are curious.

Hot water is stored in tanks, with about 10-15 kWh energy in each Solahart tank. Each Solahart system costs about $6K installed (panel and tank). To store 10 kWh using batteries would cost $13,000.

Solar thermal panels are about 90% efficient at converting solar radiation into hot water. PV panels are about 15% efficient in converting solar radiation into electrical energy.

Propane is competitive with electrical energy at about $0.25-$0.35 per kWh equivalent in our hot water heaters.

Walkthrough: Bring along FLIR camera

4x10' panel: note size, materials, if sunny hot water flow

Anna's: passive, note propane flash heaters, thermosiphon

Carter: active, note large storage tanks, pumps, sensors, insulation

Cottage 5 (if possible): note insulation, check with FLIR


Questions:

  1. If a passive solar thermal system costs $6,000 and captures 15 kWh per day of energy, with a lifespan of 30 years, what is the ROI and TCO for this system?
  2. If insulating your hot water heater at your home saves 25% of the heat lost, costs $30, and your 4500 W heater is on 4 hours per day, what is the ROI for your insulation project?
  3. If your insulated hot water heater runs for 20 years, what was the TCO for your insulation project?
  4. If you split the TCO 50% with your parents over the lifespan of the heater, how much could you pocket?
  5. What are the advantages and disadvantages of each type of solar hot water system?

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Energy conservation

Putting it all together:
Energy is a 3 legged stool:
1. Harvesting: solar (PV and solar thermal), wind, geothermal, tidal, hydro
2. Storage: Hydrogen fuel cells, Concentrated solar thermal (CST), batteries, pumped storage hydro (PSH)
3. Conservation: energy efficiency, insulation (house and hot water heater), buildings, transportation
Smart grid ties all three of these together.
Metaphor- think of food: harvest the food, store the food, don't waste the food.

What is a smart grid?
1. resource aware
2. demand aware
3. time aware
4. storage capacity
5. load balancing/shedding

Conservation topics:
Energy audit (sources, loads, times, fingerprints)
Environmental audit (sound, air, lighting, etc.)
Social aspects (penalty or reward?)
Old testament approach: bad guys and good guys-not very effective, alienates those who can make change happen
Better: graduated approach

HPA Energy Audit:
Go to elab2.hpa.edu (credentials in class)
Look under telemetry for "HPA Energy"
Main buildings: IT, GPAC, Pool, Tennis, cottages, VC
Look for trends, max and min, times and fingerprints (ask Jacob)
Mauna Lani example
Energy lab example: consumption and production

Hands-on example: heat camera
Footprint demo
Hot water container demo
Hot water heater demo
Refrigerator demo

HPA campus environmental audit: LEED and LBC
Sound
Light
Air Quality: CO2, ACH (air changes per hour), RH, temp (other schools look for Radon, VOCs, CO as well-we are passively ventilated, so these are likely to be low, we will test for them anyway)

Check this out:
Download file "01352d LEED for Schools Checklist.pdf"
Click for full-size image

Energy literacy worksheet

  1. What is the night time energy load for our campus?
  2. How could we reduce this?
  3. Now that you have access to such fancy data gathering, what would be your plan for making HPA energy neutral?


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Nuclear Energy

Nuclear Energy

Recall that since the beginning of steam driven electrical power generation, all we needed was something hot (wood, coal, oil) to boil steam and push a fan (turbine) which turned a generator. Nuclear power uses heat from a nuclear reaction.

Basics:

Fission is the splitting of heavy atoms into lighter ones. Note heavy atoms (e.g. Uranium, Plutonium, Thorium) split into lighter ones (Krypton-kills Superman, Barium-what they do with dead people):


This happens quickly in an atomic bomb, slower in a nuclear power plant.

If you are into physics, the energy comes from the binding energy of the heavy nucleus, so we call it “nuclear energy”, E = mc2 is the famous formula for this energy released from the loss of mass (the mass of the smaller ones combined is less than the mass of the original atom, this missing mass is released as energy).

Important: count the number of neutrons in (1) and the number out (3). A nuclear chain reaction happens like this:


See how the number of neutrons increases with each collision? This happens in a fraction of a second, which is useful in a bomb, but hard to control with human reaction times in a reactor.

For this to be effective in a power plant, the neutrons need to be going slowly: (“thermal” neutrons).

In a nuclear power plant, to keep this reaction going, and control the speed (slow), we need to absorb some of the neutrons, (“criticality”, one neutron in, one out), and slow these down to make their collision with the next Uranium atom effective.

Moderators are how these neutrons are slowed and controlled, usually water in the reactor, graphite control rods or other materials.

Big picture:

Good: lowers carbon emissions (none), air pollution (mercury, sulfur, other heavy metals from coal or oil)

Bad: nuclear waste, accidents (“China Syndrome”), terrorism (dirty bombs)

Three critical (public) nuclear reactor accidents:

Background:

Fission reactors were first used to power stuff in submarines (lots of cooling water). This design was not changed much when it was adapted to land-based power plants, usually situated near rivers or oceans for access to lots of cooling water. They were also made much larger using the same design, which makes for trouble.

We need to understand two main types of nuclear reactor:

PWR: Pressurized water reactor (most common)

BWR: Boiling water reactor (e.g. Fukushima)

PWR reactor diagrams:


This looks complex, here are the steps:

Fission happens when the neutrons from the fuel, slowed by the control rods and water, heat the water in the primary loop.

This hot, radioactive pressurized water passes through another secondary water loop, heating that water to make steam, which drives the turbine.

The “dead steam” is then condensed in cooling towers if on land, or using cooling river or ocean water to go back into the secondary loop.

Plus: Safer because the radioactive primary loop is contained in a containment shell

Minus: more complex, if the water boils out, the plant can meltdown, causing the China Syndrome, where the molten fuel would melt through the crust, supposedly “to China”. Some people never studied Geology.

This has happened several times: Three Mile Island in Pennsylvania, Chernobyl in the Ukraine, and Fukushima in Japan, which was a BWR reactor.

The spent fuel from both of these reactors, which is replaced every few years can also melt down if not cooled. This is still an issue in Fukushima where the cooling ponds are leaking into the ocean.

BWR Reactors:

n.b. one loop, everything else is similar.

Neutrons are slowed by the water flowing through, so as the water boils, the gaseous steam slows the neutrons less effectively, so the reaction slows down. This sounds more automatic, but this can go crazy if the water pumping system fails, as it did in the tsunami that flooded the Fukushima plant in Japan after an earthquake.

Plus: simpler, somewhat self regulating

Minus: lots of radioactive stuff to dispose of, e.g. everything (pumps, turbines, condensers, pipes, water, tools, equipment)

USSR tried using molten sodium as the coolant, the plant exploded taking a town with it.

Other types:

Breeder reactor: creates energy, but main purpose is to produce Plutonium for bombs by enriching other elements with neutrons.

Gas reactor: also known as a VHTR or very high temperature reactor. These can either be next-generation pebble bed reactors like in the e2 video, or very high temperature reactors that skip the turbine step and instead use heat to split water (pyrolysis) into hydrogen and oxygen, which can be used as fuel.

Fusion energy (the other nuclear energy):

If fission is splitting heavy atoms into smaller ones, if you can push two light elements together, you can FUSE them, releasing huge amounts of energy:

This happens at high temperatures and pressures, like in the core of our sun or other stars.

To do this here on earth, we can do one of two things:

  1. Heat and pressure from lasers aimed at a drop of deuterium (H2/1) can fuse at a temperature of 1,000,000°C (SHIVA, TOKOMAK)
  2. Use atom bombs (fission) around deuterium (H2/1) or tritium (H3/1) to make a “hydrogen bomb” or "thermonuclear weapon" (thermo=heat).

The bombs you have heard of at Trinity (first atomic bomb test), Hiroshima and Nagasaki were all fission “A-bombs”. Nagasaki used Plutonium (easy to produce, hard to explode), the others used Uranium (hard to produce, easy to explode). We only had enough Uranium for two tests, we had lots of Plutonium.

Both of these released huge amounts of radioactive fallout, covered below.

Fusion “Hydrogen bombs" or "H-bombs” are hundreds of times more powerful and destructive "thermonuclear" weapons.

The ones you see in tests on the ocean are H-bombs.

Present use of A-bombs is only in small cases, or in “neutron bombs” which are designed to release neutron radiation, killing people, leaving buildings intact (banned in the 1970's as inhumane, developed to defend Europe if the USSR invaded).

Fusion power would be great, as the oceans have lots of Deuterium. It is also much cleaner. Ignition is the toughest part, check this out:

National Ignition Facility-SHIVA

Radiation and Fallout:

Recall four main types of nuclear radiation:

Alpha particle/rays: slow, heavy Helium nucleus, charged, stopped by your skin, but if it gets inside (lungs or blood) they are fatal.

Beta particle/rays: faster (137,000 mph), lighter, charged electrons, stopped by metal foil, can knock electrons off of DNA, so these are called “ionizing radiation”.

Gamma particle/rays: speed of light (675,000,000 mph), no charge, no mass, ionizes DNA, stopped by lots of lead or concrete. Very dangerous.

Neutron radiation: heavy, uncharged particles destroy cell membranes, make steel brittle, passes through many meters of lead of concrete.

Radiation comes from anything radioactive. Fallout is the name for dust or particles of this radioactive material.

Two main cases:

  1. Bombs: release radioactive materials from the bomb, but mainly lots of dust from vaporized islands/desert/other stuff. “Dirty bombs” are just explosives with lots of radioactive stuff wrapped around them (e.g. plutonium, cobalt, cesium, radioactive waste)
  2. Reactor accidents: usually much more radioactive material involved (1000 kg vs. 10 kg), less of an explosion vaporizing stuff, more a matter of radioactive fuel exploding and going into the atmosphere.

Hiroshima, Nagasaki: radioactive dust, Plutonium (Nagasaki), many mutations from radiation: direct (alpha, beta, gamma, neutron) and fallout (usually alpha, beta, gamma).

Pacific bomb tests: US tests obliterated some of the Marshall islands. The French tests near Tahiti released lots of radioactive Strontium 90, which radiated dairy products in NZ (look up Strontium and Calcium on the periodic table). The French are not popular in that region. Side note: the French later bombed a Greenpeace ship, the Rainbow Warrior in Auckland Harbor in 1985 which was protesting these French bomb tests. Again, not very popular.

Three mile island: 1979: A water valve malfunctioned, due to human error the core was uncovered, the core then melted down, radioactive gas was released from the containment dome, no deaths, but a 5/7 on the total nuclear disaster scale. This happened the same weekend a movie about the same accident opened: The China Syndrome

Chernobyl: 1986: During a rogue test (more human error), the graphite/uranium core exploded, radioactive core materials, Iodine 131 and other radioactive isotopes were released, many tons of highly radioactive dust were released all over Europe (detected even here in Hawaii). Toll: 28 dead on scene, 200,000 estimated cancer deaths all over Europe. The USSR hid the disaster for days, which was finally detected at a nuclear facility in Sweden.



Fukushima: 2011: The 9.0 Tohoku earthquake offshore caused a tsunami that flooded and disabled the power plant pumping the BWR reactor cooling water, the core melted down, then exploded, the core is still molten today, TEPCO (Tokyo electric power company, the power utility) continuously lied about the accident, and is still trying to contain the leakage into the ocean and groundwater. All fish and produce from the area is still banned.



Smaller accidents: Sweden: Forsmark, Japan: Tokaimura, SL-1 Reactor Idaho Falls (three victims were buried in lead coffins they were so radioactive)

Make sure you understand half life:

At = A0 (1/2)n or At = A0/2n

At is the amount later at some time t

A0 is the amount at time zero

n is the number of half lives

Common misconception about half life: 2x half-life does not make zero

Can also use population formula if you want to show off:

At = A0e-kt if you know k (the decay rate)

k = 0.693/t1/2 n.b. as t1/2 is larger, k is smaller (slower decay)

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e2:coal and nuclear

SALT audio: Jim Woolsey, June 26, 2010 NPR


Coal and nuclear:

http://physics.hpa.edu/physics/apenvsci/videos/e2_videos/e2%20energy/6%20coal%20and%20nuclear.mp4

APES questions


  1. Jim Woolsey in the audio describes a power shift, using salt as an example-explain
  2. What has changed in the energy picture since this was aired (2010)?
  3. What are the three main uses of energy in our country, according to the audio?
  4. How will smart grids and electric/hybrid vehicles impact this?
  5. Why a perfect storm?
  6. When he says “our grandchildren” who does he mean to you?
  7. Why a silver bullet? what is this reference?
  8. What percentage of global energy is sustainable?
  9. Why are coal and nuclear "two 800 lb gorillas"?
  10. Wood to coal-why and when? why is it the 21st century energy source?
  11. How has this changed since this video was created in 2008?
  12. Coal plants: how often are new Chinese coal plants opened, how long will each one last?
  13. Mercury, sulfur compounds-why and to whom do these impact?
  14. Who does Mike Mudd represent? Is he telling the truth?
  15. Jeffrey Sachs stresses testing-why? What have we found about carbon capture?
  16. Carbon capture-why is it dangerous?
  17. Why do you think the Montana folks want to promote carbon capture?
  18. Susan Papalbo says we could capture CO2 for hundreds of years. If the cost of carbon capture makes coal even more expensive in competition with cheaper natural gas, do you think this will still go through?
  19. For how many years could coal provide US energy?
  20. 2100 mW for how many homes? How much for each home?
  21. What does Dan Kammen think about carbon capture?
  22. 1.8 million tons of CO2? for what time period?
  23. Why does the pursuit of carbon capture slow development of greener solutions?
  24. This video is from 2008, what has changed since then that dramatically changes the scene to the use of coal for electricity?
  25. Look up “Future Gen” the IGCC system and see how it worked out.
  26. The coal guy says 2012 is when it should be running-what happened?
  27. How much energy in the us is created by nuclear plants?
  28. Jeffrey Sachs compares coal and nuclear-what does he think?
  29. This video was done before Fukushima Daiichi in Japan. How has public opinion changed since then globally?
  30. Why is a pebble bed reactor safer? How does it differ from a traditional reactor? (look this up)
  31. How is the nuclear waste issue in a PBR differ?
  32. What is NGNP?
  33. What is the LEGO construction model?
  34. Nuclear power plants cost many more times as much to decommission as to build. how does this impact investment?
  35. How many permits for nuclear power have been approved in the last 30 years?
  36. if you develop a solution for these, what will the impact of this be?
  37. What is meant by an “Energy Portfolio”?
  38. Why is Jeffrey Sachs an optimist? Are you part of his vision?

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Energy Primer

Energy primer

Energy and power units:

kW means kiloWatt, kilo = 1000 Watt named after a person, so capitalized

1000 Watts = 1 kW (note spelling)

kW is a rate, like miles per hour or gallons per minute, so saying "kilowatts per hour" makes no sense, just like "miles per hour per hour"


To get total energy (or miles or gallons) we multiply by time:

1000 Watts for one hour = 1 kWh (“one kiloWatt hour”)

Example: a 1000 Watt hot water maker is on for one hour

1000 W = 1 kW times 1 hour = 1 kWh


KVA is another unit similar to kW, but it includes what is called the power factor.

For simple things like hot water makers or toasters, PF (power factor) = 1.00, meaning 100% of the electrical energy goes to work.

Motors, compressors, refrigerators, computers and pumps can have power factors as low as 50%, meaning if you think the device is using 1000W, you are really paying for 2000W.

HELCO charges us a premium if our campus total PF is less than 90%

HELCO charges us about $0.40 (40 cents) for every KVA, so if you have an energy number, you can round to about half of this number to convert to dollars (neat tip).

Note on units: Watts, Volts, Amps (Amperes) are all capitalized. Don’t capitalize meters, hours or gallons.


Lighting:

We are in the 4th generation of lights in this country.

~1850 incandescent lights (Edison and his gang). These look like hot wires in a glass envelope

Most energy goes to heat, so not efficient, simple to operate, PF 1.00 (just a hot wire, like a coffee heater)


~1950 Fluorescent lights (note spelling: flUOrescent, like FlUOrine)

More efficient, contain mercury (toxic), need a transformer (hot, noisy)

Related: mercury vapor (white) and sodium vapor (yellow) lamps, also known as metal halide lamps, often found in streetlights, gyms, tennis centers. PF is about 80%. Many of these are being replaced with LEDs (see below).


All of these create an electrical arc through a vapor of metal (even fluorescent bulbs, which contain mercury and a phosphorus inner coating to transform the harsh mercury light into visible light)


~2000 Compact Fluorescent bulbs (CFL)

Similar to traditional long or circular bulbs, but able to screw into 1850 era light sockets (yes, they are that old).

Contain mercury and phosphorus, 3-5 year lifespan, PF ~80%, often a harsh white/blue light, as opposed to the warmer hot incandescent light bulbs. This color is referred to as a temperature, so 2000°K is a warm looking source, while 3500°K would look harsh and blue-tinted.


~2010 Light Emitting Diodes (LED)

Very efficient, can be many colors, little heat, long lifespan, PF close to 95%, uses about 65% less energy than traditional bulbs, relatively expensive, but long lifespan makes for excellent ROI and TCO (return on investment, total cost of ownership). These vary in temperature (see above), with newer LED units in the warmer 2000°K range, where older ones tended to look blue and harsh, often around 3500°K. Newer ones are also dimmable.


~2018 Smart LED bulbs

Same as above, but linked through wireless or power lines to controllers, so you can say "Hey Siri, turn on the lights" and magic will happen. These are key to the smart home, where sensors for lighting and occupancy can control lighting, saving energy, and therefore money.


Conservation:

Every dollar spent on conservation is worth about $8 in new energy sources.

Monitoring is key, to determine energy flows, leaks, identity (energy profile) and more.

This can be electrical metering, infrared cameras, flow meters, propane meters, water meters, temperature sensors and other linked data gathering devices.

Key targets are refrigeration (e.g. cafeteria), water pumps (e.g. pool), lighting, water heating and timing-when these resources are used relative to energy harvesting.

Especially important at night, when PV and solar thermal systems are dependent on storage (the sun is not shining much at night).

Solar thermal:

Goal: Turn solar radiation into hot water

Active systems: Sun—>solar panel—>pump—>tank—> users

Passive systems: Sun —>solar panel/tank —> users (no pump needed, uses convection)

HPA systems are of two types:

Carter dorm has the active system, while Perry-Fiske and cafeteria have passive Solahart systems

Propane is used to finish these systems, making sure that users always have hot water at about 120°F. These are propane "flash" heaters, making sure that any water going to the showers/sinks/washers is always at 130°F. You can see these behind each bathroom if you are curious.

Hot water is stored in tanks, with about 10-15 kWh energy in each Solahart tank. Each Solahart system costs about $6K installed (panel and tank). To store 10 kWh using batteries would cost $13,000.

Solar thermal panels are about 90% efficient at converting solar radiation into hot water. PV panels are about 15% efficient in converting solar radiation into electrical energy.

Propane is competitive with electrical energy at about $0.25-$0.35 per kWh equivalent in our hot water heaters.


PV (photovoltaic): light to DC electrical energy

If solar thermal captures solar radiation as heat, PV systems convert this radiation into electrical flow in one direction (direct current, or DC, like batteries). This is convenient for battery storage, but to be used in most homes and businesses, AC (alternating current, 60 Hz) is needed. Inverters are electronic devices that turn DC from PV and/or batteries into AC for use.

Since HPA is on one meter with HELCO, we are essentially a “micro-grid” meaning any electrical energy harvested from PV (or released from batteries) goes to slow down or reverse the HELCO meter. Since we do not presently get any credit for energy out, we want to make certain we can store any excess energy on campus for our night time use.

Since the sun is brightest at noon, PV engineers use an estimation of a PV array output called “solar hours”, meaning the equivalent amount of energy harvested if noon lasted that many hours. This is like making a camel hump curve into a rectangle, adding the edges to the top.

For example, our PPA (purchase power agreement) array behind the elab produces about 100 kW maximum. This is true at noon, but less so either side of noon, so we use “solar hours” to estimate energy harvest each day. For us, this is about 5.5 solar hours, depending on season:

100 kW x 5.5 solar hours = 550 kWh or about $200 saved each day.



PPA arrangements usually charge us a fraction (about $0.20 per kWh) of the HELCO cost, but we have to pay for what it produces, not what it uses. If we are pushing energy out the door to HELCO using the PPA array, we are in effect paying to give this energy away, which happens during vacations (summer, winter, spring).

Net zero energy is when we have effectively stopped the HELCO meter, meaning we are producing exactly how much we are using.

We hope to harvest enough to reach net zero around 10AM each day until about 2 PM each afternoon. The extra energy during that time we hope to capture using battery and other storage systems (pumped storage hydro, hot water activation, etc.)


Energy Storage:

Batteries for large scale systems are usually either lead acid batteries dating back to around 1800, or lithium batteries from this century:

~1800 lead acid batteries

lead and sulfuric acid

environmentally nasty

3 year lifespan

shorter if used more

only 40% of capacity is usable

slow discharge and recharge

about $300 for each kWh stored


Example: our overnight campus use is about 100 kW for 20 hours or 2000 kWh (or 2 mWh). At $300/kWh this would cost us $600,000 and would last 3-5 years at max capacity, but in actuality it would be 2.5 times this because these batteries cannot be discharged all the way, so $1.5M.


~2010 lithium batteries (LiPO, Lithium iron phosphate, etc.)

Used in Prius, Leaf and other cars

lightweight

fast discharge and recharge (good for regenerative braking in cars)

20 year lifespan at 80% capacity

greener

expensive ($1300 per kWh)

Tesla's Power Wall is one example, so is the blue box in the student union and IT office. Kauai island is using these to move that island to complete energy neutrality in the next few years.


The same example above costs more, last longer, and requires fewer batteries. It also discharges faster to maintain our microgrid, and recharges faster when used as backup power for the IT building, protecting our computers from multiple outages we face with HELCO.


Pumped storage hydro:

Water tanks low on campus have a pump and a generator. When we have extra energy, we pump this water uphill to a similar tank where it is stored for use later on. When needed, the system activates the generator, which provides power for the campus. This is green, cheap, renewable, lasts 50 years or more and can be safely integrated into other water systems (e.g. fire suppression) as needed.


Net neutrality:

We have three ways we can claim neutrality:

  1. Net energy neutral: We export the same amount of energy around noon that we use overnight, so as far as the HELCO grid is concerned, we have a net zero energy profile. We still pay for what we use at night, though)
  2. Net money neutral: We capture any excess energy during the noon hours when the HELCO meter would be spinning backwards, and use this at night from our batteries or other storage). If we were allowed to sell power to the grid, this would also work.
  3. Net carbon neutral: We measure all carbon used on campus, including transportation, heating and other carbon impacts and offset with energy produced via solar thermal, PV, wind or other means (not nuclear, don’t worry). This is the most current global metric used, and relates well to our sustainability misssion.

Each has certain PR and moral aspects, depending on the goals of the organization. Since our business is creating change agents to solve sustainability issues in the future, each of these is important.


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In hot water!

In our last test, we measured the power in Watts of several hot water heaters.
We were also able to calculate power in Watts by multiplying Volts (electric potential energy) by Amperes (electric current, also known as "amps"):

Power (Watts) = Volts x Amps

This only works for devices that just create heat, like ovens, hot water heaters and non-induction stoves.
These are known as "ohmic loads", since they don't have any magnetic fields or other complexities, like motors or power supplies.

Another way to calculate power is by using an Ohmmeter, which measures resistance to electric current in Ohms (another dead dude, so we use capital letters)

Try this:
Use the ohmmeter (symbol looks like a horseshoe) to measure electrical resistance across your hands.
Try it with more than one person.
Questions: Why does it fluctuate? Why does it not hurt? How does this thing work? Why do they use this as a lie detector?

Back to the hot water tea maker:
Measure and record the resistance of the tea maker in Ohms .
Power can also be calculated by:
volts x volts/R where R is resistance in Ohms, or V^2/R

Connect your hot water tea maker through the little Kill-a-Watt meter we used before to measure power, current and voltage.
How close was your calculated value for power to the one measured?
What was the current you measured in Amps?

Another fun way to calculate power is this:
Power (Watts) = current x current x resistance, or i^2R
Calculate the predicted power of the tea maker using both of these formulas, and compare to the measured values on the little grey meter.
---------true power part----involves water----
Next, let's see how much power in Watts the hot water tea maker actually produces.

Measure out 1000 ml of cool water in each tea maker (you can see the amounts on the side of each unit).
This is one liter, and has a mass of 1000 grams.
To heat one gram of water one degree C, you would need one calorie (this is the definition of a calorie).

Measure the temperature of your cool water, and turn on the heater, recording the start and ending time, when the water boils. We can assume this happens at 100 °C.

The change in time is in seconds
The change in temperature is ∆t and should be in °C

Calculate the amount of joules of electrical energy you added to the water like this:

Energy (joules) = Watts (joules/second) x seconds (use the values for Watts on the grey meter)

Now it takes 4.18 joules to equal one calorie, so convert your joule number into calories. This is your electrical energy conversion number.
Record this:

From the hot water measurements, heat energy (calories) = mass (grams) x 1.00 (water number) x ∆t (degrees C), or:

Q = mc∆t

(you may be seeing this in chem class this week)
Calculate how many heat calories your hot water heater delivered to the cool water.
m = mass (should be around 1000 grams for your test)
c = 1.00 (definition of water specific heat)
∆t = change in temperature, from starting temp (around 20 °C) to boiling (100 °C)
How many heat calories did the water absorb?

Divide the heat energy number by the electrical energy number. Is this greater than one? Why/why not? What does this number represent?

Now, take this to a bigger scale:
Your home hot water heater has a capacity of about 50 gallons, or 200 liters.
How many grams of water is this?
If the water comes in at 20°C and you want hot water at 70°C, how many degrees warmer is this?
How many calories is this?
How many joules is this?
If your hot water heater is 4500 W (this is 4500 joules/second), how long will this take? (divide the joules by 4500j/s)
How many kW is this?
How many kWh is this?
How much will it cost if HELLCO charges us $0.35/kWh?
How much per month is this, if it happens twice a day?

How could solar thermal panels change this?

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ch 17 little froggies

Energy!
Chapter 17 in the Frog book has a nice intro to energy, some of it old, some new, all of it totally frog-like.
Let's dive in:

Energy=the ability to do work
Heat=lowest form of energy-can only move molecules around
Primitive societies: fire from wood
Wood is scarce, hard to carry, and hard to light when wet or green, so...
Coal!
What is coal?
Millions of years ago, living things decomposed, some around oxygen, some without oxygen.
If a living thing is made of C H and O, and the water leaves, what is left?
Carbon (coal)
This enabled the industrial revolution to happen: burn coal, make steam, make stuff move around.
Up to this point, you had to be near a river to have a mill. With coal, you could do this anywhere you could drag a humongous pile of coal with you...
Steam can also move fans, or special fans called turbines, so you can make electric generators move (you can also do this with moving water, which is what hydroelectric power is all about).
Back to Energy.
It is measured in some pretty inventive names: Joules ("jowles" if you are British), ergs, calories (like in chemistry, or food, where 1000 cal = 1 Cal), or kWh (this one is really goofy).
Now, what is the difference between energy (the ability to do work) and power?
Power is how FAST you can do the same work.
Imagine two students climbing a ladder to the roof of the elab, 10 meters high. Both have mass 100 kg (big folks, around 220 lbs.).
One climbs up and does this in 10 seconds.
The second one takes his/her time, taking 100 seconds.
Here is how a physicist would calculate this:
Work = energy = mgh = 100 kg x 9.8m/ss x 10 meters = 9800 joules (same work for both)
Power is work/time, so one does it with 9800/10 or 980 Watts (this is over 1 hp, 1 hp = 747 Watts)
The second does it in ten times the time (say that fast), or 98 Watts, about enough to keep a fan running...
Check this out:
https://www.youtube.com/watch?v=S4O5voOCqAQ

Your turn: measure the time it takes to boil some water in the hot water makers. Note the Watts for each, as well as the time it takes to do this work.

What you are measuring is Watts, convert them to kiloWatts by dividing by 1000.
If you have a 1200 W heater this is 1.2 kW.
Now for the time. You have to convert time into hours, so divide seconds if you measured these by 60, then again by 60 to get hours, or you can divide seconds by 3600, which is the same thing.
Multiply kiloWatts x hours to get kWh, or kiloWatt-hours.

This unit is a goofy one, created so we could measure electrical energy consumption.
Quick: which one is power and which one is energy? Watts or kWh?

Here is something interesting to ponder:
HELCO (Hawaii Electric Light Company) charges us about $0.35 per kWh.
You can estimate this as about 50 cents for most uses, since this is often the value.

So, if your roommate leaves her 1000W curling iron on 24 hours a day for 180 days of school here, how much would this cost the school? (yes, this really happened).

Back to power:
This we know is measured in Watts (named after some dead British dude).
It can also be measured in horsepower, where about 747 Watts = one horsepower (yes, that means equivalent to the power of one horse, so our climber was stronger than a horse, so was Robert Forstemann, which is CRAZY).
Look up the guy who pedaled the first self powered airplane over the English Channel in 1979-how many HP did he create, for how long?

The electric company, natural gas company, gasoline company and water company don't care how FAST you use their stuff (electricity, gas, gasoline or water), they just care how MUCH you used, so:
Electricity = kWh
Gas = liters or gallons
Gasoline or diesel = liters or gallons
Water = gallons
BUT
If you have a really powerful car (lots of horsepower) you will likely use your gallons of gasoline faster.
Make sense?

Our goal in conservation is to use as few joules, calories or kWh as we can.
How?
Next: Conservation.

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Hot water lab

Hot water lab:

Part 1: hot water

  1. Plug the water heater in to a kill-a-watt unit, note all values: voltage, power, current, power factor
  2. Start the water heater, timing it until it boils, measure all units again
  3. Calculate the kWh used by the heater: kW x hours (you may want to use minutes/60 to get hours)
  4. Calculate the cost to heat that much water, using $0.40 per kWh.
  5. If your hot water heater at home runs for 2 hours per day using 4500W, how many kWh is this?
  6. If HELCO charges $0.40 per kWh, how much would this cost per day?
  7. Per month?
  8. Per year?
  9. How would solar thermal panels impact this number?

Part 2: VOM use

  1. Battery voltage, AC or DC? Measure the voltage from the PV panel outside.
  2. Line voltage (~) AC or DC? Measure the voltage of a wall plug.
  3. Resistance: Ohms (Ω) symbol. Hold one lead in each hand, does the value change? Why? Make a chain of hands and try the same thing.
  4. Measure resistance in ohms of water heater. This is called an "ohmic" load, because it only creates heat, not motion or energy change, like a motor, or power supply.
  5. Calculate power of the heater in Watts using P =IV, = i2R = V2/R. Make sure your units are Volts, Amperes, Watts and Ohms.
  6. Compare with your results using the kill-a-watt unit to measure power under load (e.g. when heating water). Same or different? Why?

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Energy primer

APES notes Energy

Renewable energy on our campus:

Solar PV: radiation from the sun (visible) making electrons move in a special semiconductor material (silicon, made from sand), so photo (light) voltaic (Volts) = PV or photovoltaic. These release direct current (+ and -) energy like a battery. To be used in our electrical system, we use an inverter to change the DC to AC (alternating current). Inverters are large boxes that are usually hot when in use. PV panels are usually made of glass, often with a purple color, which is the semiconductor below.


Solar Thermal: radiation from the sun (visible) hits a dark metallic surface (often copper or aluminum, since they conduct heat well). The dark surface transforms visible radiation into thermal (infrared) energy, which is conducted by the copper or aluminum to attached water pipes. To keep the heat energy from radiating away from the panel, the metal is coated with a special paint, and covered with a special glass insulating layer. The glass is the heaviest part!


Wind energy: Solar radiation (mainly visible) heats the surface (water or ground) which makes the air in contact with the surface less dense, so it rises into the atmosphere. Wind is the movement of air to replace this rising air. Since air has mass, when is passes over a surface that can move, the kinetic energy of the wind (1/2mv2) can push a wing. Two or more wings working together will rotate a shaft that can be connected to a generator (Direct current, DC) or an alternator (alternating current, AC). Turbines can be horizontal axis (HAWT) or vertical axis (VAWT), which are less popular. Horizontal axis turbines can be leading or trailing, meaning the blades are in front of or behind the tower. Most large turbines are leading, because of the turbulence from the mast.


Storage:

Hot water: the cheapest energy storage method is hot water, usually from solar thermal panels, but can also be from PV panels running a traditional electric hot water heater, just like a coffee maker. Insulation is a key aspect to hot water storage, as heat travels from hot to cold through conduction (contact) radiation (radiation) or convection (hot air rising). Most hot water heaters are insulated (conduction), reflective (radiation) and covered (convection).


Batteries: These can be old style lead acid batteries like those in a car or golf cart, or newer lithium batteries like those in electric vehicles or in our IT and student union setups. Batteries only store Direct Current (DC), so they must go through an inverter to supply the grid, which is alternating current (AC). Energy stored in a battery can be as cheap as $100 per kWh stored for lead acid batteries, or up to $500 per kWh for lithium batteries, which charge much faster, last longer, and are much better for the environment than lead acid batteries.


Hydrogen: Passing direct current energy through water splits the water in to its components, Hydrogen and Oxygen. If the Hydrogen is captured and compressed, it can be used to burn for heating, cooking or in vehicles, or if passed through a special Fuel Cell membrane into direct current electricity, just like a battery as well as hot water. This is not as efficient as a battery, but can be used for long term storage.


Conservation:

Every dollar spent on conservation is worth 8 dollars in new renewable energy systems. Some key places to conserve energy:

Hot water insulation and timers

Passive ventilation vs. air conditioning

Lighting LED and passive

Vampire load reduction

Smart use of resources, occupancy based energy use


Energy units:

1 Joule is the basic unit of work or energy

1 Joule used or produced every second is called a Watt, so 1 Watt = 1 joule/sec

1000 Watts is 1 kiloWatt or kW

1 kW used or produced for one hour equals one kiloWatt-hour or kWh. A truly goofy term, but something easy to measure:


1000 Watt coffee pot running for 1 hour: 1 kW x 1 hour = 1 kWh

This is attached to cost, so the electric utility may charge you 2 cents for a kWh in Oregon, or 45 cents per kWh here in Hawaii-why?

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