# Energy-projects

Energy Curriculum notes

8.2016

VOM meter: 2 lead VOM, e.g. Fluke Model 114

Measure ohms short and open

Measure ohms across chest (can calculate fatal voltage here if current is known)

Measure ohms around circle of students, break circuit (circuit concept here: need two wires)

Define "circuit"

Measure voltage across chest-why does it vary? (EKG concept, can extend to differential EKG)

Measure DC voltage of small batteries (learn what symbols for DC and AC voltage are on the meter)

Measure AC voltage at outlet (caution here)

Explain why dry hands are better, cross body shocks, grounding

Measure resistance from hands to ground

Electrical safety unit…

Kill-a-Watt unit

Ohmic loads: tea maker, coffee maker (make sure water is cool)

P=VI

P = I2R

Measure voltage at outlet

Measure resistance of ohmic load with VOM

Predict power used, current

Power measured/power calculated = ?

Repeat with vacuum cleaner or other motor device

Recalculate power calculated vs. measured

P = VI again, vs. power measured

Try the P.F. button

Light bulb analysis:

Incandescent bulb: measure R with VOM, measure power with KaW unit

CFL: repeat

LED: repeat

Next measure light output for each, compare with power used (measured with KaW unit)

Cost to run:

Calculate cost to use each bulb for 1 hour, define kWh.

Calculate cost to run tea maker for 1 hour, define kWh.

Calculate savings between LED, CFL and incandescent bulb, per day, week, month, year, over lifetime

Define ROI and TCO

Renewable energy:

ROI and TCO

PV, Wind and Solar thermal

ROI is time to pay off device (in days, months or years)

TCO is total cost of ownership (should be negative)

Data from websites or hands-on if available

Efficiency evaluation

PV panel

Measure incident solar radiation (or from weather service) in W/m2

Measure output of PV panel, using ohmic load (resistor or tea maker), current, voltage

Calculate % efficiency

Solar Thermal Panel

Solar thermal same incident solar, measure temp in and out for solar panel, and time to fill 1 liter container (flux)

Use mc∆t to calculate calories captured/harvested, 4.18j = 1 calorie, j/s = Watts

Wind turbine

Difficult with varying wind, you may be able to hold small turbines while driving a truck (this is how some are actually evaluated)

Area of turbine is needed, and wind speed, altitude (air density) as well

Look up Betz coefficient, 0.39 is max (why?)

May be done using data from manufacturers

Residential energy audits

TED units (theenergydetective.com)

Installed at houses, classrooms

Measures predicted billing, uses, trends

Excellent for articulating with commercial energy audits

Control by web units, using current transformers

CBW analog units process 8 analog 0-5Vdc inputs to web interface with logging

CTs are Hawkeye 922 units (0-5 Vdc output), with 30,60 and 120 Ampere rating

Larger ones as well

Assume PF = 1.00, calculate Watts from P = VI (assume voltage constant, but measure accurately to calibrate)

Energy Lab server

elab2.hpa.edu

Telemetry of campus or remote locations

Can interface with CBW units globally, as long as they have access to internet

Used in "energy hunts" finding lights or loads hidden around buildings