Powering My House From My Car
(not vice-versa)
Internet Cowboy Un-Conference
Jackson, WY 7/16/11
by Gary Lauder
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Problem Statement
• Put in solar PV in 2001 due to rolling blackouts
– When Enron was gaming the system
• Done for backup power, so included batteries
– Much much more complicated than standard
• Past decade's grid reliability has been excellent
• Power drain to maintain charge state significant
• Time to replace batteries, so decided to:
– Use fewer batteries so would not last the night
– Add generator to sustain power when w/o sun
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Generator issues
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Natural gas supply likely cut in big earthquake
Diesel tanks can leak, need refilling, smelly
Where to locate? (noise, refueling, space)
Was pondering problems...
Unrelated activity: gave short TED talk in 2010
Similar idea
• I was contacted by someone (Richard Factor)
who had similar idea:
PriUPS
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His web site was www.PriUPS.com
= Prius/UPS
Prius batteries: 200-230V
Feed into voltage converters to 48V
48V feeds into existing solar inverters
Some Soldering Involved
Voltage Conversion Box
Orange Cables
Connect to Cars
4 Inverters
convert 48V to
120/240V
Installed
Connector to
Car's HV
Battery
Thermal IR Image of Conversion Box Wires
Stats
• Tested at 3KW/car (more than I need)
• I think I can double that output/car
• Uses 1.7 Gal./hour = to driving at 31.5 MPH, so
tank lasts 7+ hours if operated full bore
• If gas costs $4.00/Gallon
• Using PriUPS costs $1.59/hour
• Cost of electricity is $0.55/KWH
• With less power consumption, rate of gas usage
declines
• Many thousands of $'s less than traditional gen.
Thank You!
Gary Lauder
Gary@LauderPartners.com
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