|
| Back to Contents Page |
Home Energy Index |
About Home Energy |
| Home Energy Home Page | Back Issues of Home Energy |
Home Energy Magazine Online May/June 1993
EDITORIAL
Lessons from the Electrical Frontier
More and more households are opting for photovoltaic (PV) electricity supply
systems, and with them a change in household technology and lifestyle. In fact,
a recent study estimates that at least 25,000 homes operate "off the grid,"
relying on PV to harvest electricity and on batteries to store it. However, PV
supply systems are quite expensive. Off-the-grid households effectively pay
25-75cents per kWh for their electricity. In the context of such high
rates--almost ten times the on-grid rates--the frontiers of energy-efficiency
are tested. There's a lot that those who are connected to the utility
grid can learn from those living off of it. Thus, an article in this issue
describes how one household in Arizona adapted to a photovoltaic (PV) electric
supply system.
PV-powered homes require changes in technologies and appliances. For instance,
one of the most efficient refrigerators manufactured today was originally
designed to operate with PV systems. This is because the costs of additional
solar collectors and batteries needed to supply precious kilowatt-hours far
exceeds the costs associated with standard energy-efficient refrigerators.
Similarly, fluorescent lights are the rule rather than the exception in PV
homes. The costs of switching to compact fluorescents from incandescents are
tiny compared to the savings from utilizing smaller solar panels and
batteries.
The discipline imposed by a limited supply of electricity has forced many
residents of PV-powered homes to attack insidious miscellaneous uses of
electricity: the instant-on feature in a television, LED clock displays, and
appliance power supplies that consume electricity even when the appliance is
not used. Each of these draws only a few watts but, together, they can drain a
battery without the occupants' knowledge. Even in this ultra-efficient home
these energy culprits drew a constant 27W. The craziest example was discovered
by the Arizona study--the electric ignitor in the gas oven. This particular
ignitor is so inefficient that the gas oven probably consumes more electricity
to cook a small potato than a microwave oven!
Normal utility-powered homes have their own, larger miscellaneous uses like
sump pumps, water beds, and automatic ice makers. These can add hundreds of
watts. Not surprisingly, you won't find these energy guzzlers in PV homes.
It's unlikely that electricity prices will soon climb to PV prices. Still, the
measures and vigilance that residents of PV-powered homes take demonstrate that
we can maintain our familiar lifestyle on just a few kilowatt-hours per day.
| Back to Contents Page |
Home Energy Index |
About Home Energy |
| Home Energy Home Page | Back Issues of Home Energy |
Home Energy can be reached at: contact@homeenergy.org
Home Energy magazine -- Please read our Copyright Notice
| 
