AboutMarshall Scott Expertise I am knowledgeable about residential solar pool heating, moderately knowledgeable about
residential solar electric systems, and can resource answers in solar hot water and battery back up
PV systems, but personally have little experience. I review questions M-F 7:00am - 4:30pm.
Experience Solar pool heating and solar electric systems
Education/Credentials BA in Psychology which has nothing to do with solar. Various trainings and presentations on solar and 5 years experience.
Question Hi. I am looking for a 9-month off the grid solution for 1-5 low energy use homes. Each home has a running fridge and the option for a/c and heat. Funding is available for temporary solutions until power lines are restored, but even a cheaper (!) permanent solution might be harder to get through the red tape involved here. Is there a company that rents windmills? Or solar panals of a size to suit the needs here? Daily fuel costs for the generators being used now are very high, so suggestions will carry some weight here... . Thank you for this great service!
Answer Hello Molly,
I've heard of one place that may rent wind or solar power generation on a temporary basis, although I don't know any details. I suspect it won't be "cheaper". More places may be found if you scour the internet.
Solar and wind power are available in varied levels. I have seen projects and design for generation from homemade windmill and solar panels that produce a 100 watts or so.
Sample: http://www.velacreations.com/chispito.html
There are smaller more common single use application like solar path lights, gate openers, water fountains, etc. There are also systems designed for use with RVs and larger applications like homes. As the application gets larger, the material cost and the permanence of the installation becomes much greater.
A typical small home will run about 30K for an off-grid solar system. A wind generator large enough to power a small house will require a large, tall mounting tower and multiples of guide wires to hold it in place. Besides size and permanence of mounting structures, the poor energy design of homes combined with our consumption habits for electricity usually means that a large investment is needed to offset our energy needs.
Off-grid also means storage needed for electricity. Batteries are expensive, need to be replace regularly (5-10 years based on brand and use) and will cost a electrical generation system 10-15% loss in efficiencies. Also most homes require 120V of Alternate Current (AC) and usually generation and storage is either 12V,24V,or 48V of Direct Current (DC). This means to convert the electricity an inverter will be need to supply the correct type of electricity for the home appliances.
A solar passive designed home (for heating and cooling) with electrical needs of 12V DC only (low voltage lighting, cooking, etc.) could get away with a small generation system and small storage which would accommodate what you are suggesting. In rural 3rd world countries it is common to use much smaller off-grid systems because their needs are so minimal.
As a conclusion, for temporary usage, a high efficiency, variable speed generator is recommended with a focus on conservation of energy. The money spent on high efficiency appliances would be a much wiser investment than try to offset excessive waste of electrical usage with the high cost of alternative electricity.
Sample: (notice it comes as a 12V unit) http://www.sunfrost.com/refrigerator_specs.html
