About how much would it cost to purchase and install solar panels for the average American house so that the house can be off the power grid and use the same amount of electricity as it normally does?
Homes vary tremendously in their usage. It will be a factor of 0: between a conservative house, and a heavy use one. To get the answer for your own house, check the electric bills. Also, the answer for the size of solar electric system varies with the location of the house. A Minnesota residence may get only 2/3 or /2 of what an ideal California house gets, even though both are sunny. As a data point, our California house has no air conditioning, no electric heat, no pool, and no big screen TV. We use maybe 5 - 8 kWh a day on average (more in winter, less in summer). We have a 3 kW solar array on the roof, and it roughly keeps up with our usage.
And even though the better technology is out there, it is not in mass production. Perhaps one day it will be, but it is not there presently Silicon wafer based solar cells Despite the numerous attempts at making better solar cells by using new and exotic materials, the reality is that the photovoltaics market is still dominated by silicon wafer-based solar cells (first-generation solar cells). This means that most solar cell manufacturers are equipped to produce these type of solar cells. Therefore, a large body of research is currently being done all over the world to create silicon wafer-based solar cells that can achieve higher conversion efficiency without an exorbitant increase in production cost. The aim of the research is to achieve the lowest $/watt solar cell design that is suitable for commercial production.
My friend has a system with 6 Panels, I think about 6 large batteries (Like Golf Cart Battery), a 5 KW Generator. It also has all the electronic controllers and monitors. He has about $30,000-$35,000 in his system. It does pretty good except it will not support air conditioning or heat without running the generator which is expensive. He has some niehbors that have air conditiong, but they use a gas / ammonia cycle for that. Caution, even with these systems they must be very careful with power usage, or they must run generators. They are located in the Sonoran desert where the sun shines just about every day so it is the very best of conditions. Based on this, I would say a system that would match the average household usage would cost around $80,000 or more, and would need a huge roof or large open area facing south. Probably not practicle, but possible.
We are installing a 3.3 kWh system on a 2 story house. Really three story if you add in the basement. It will provide about 3/4 of the electric power they use per year. The cost of the complete system installed is in the $26,000 range. A 4.5 kWh system would wipe out their bill and would cost in the $34,000 range installed. But it had too many solar modules to fit on the roof. Now if you are wanting to go off grid in the average American home you would spend about $60,000 easy. Most American family's are very very waste full. Very few even have CFL lighting and leave every light in the house on. I have even known of some that will use a 60 watt night light when it is so easy to put in a CFL or a 4 watt night light. With 4 TV sets running in most homes at the same time a 200 watt stereo system for background noise.. Well we Americans have a long ways to go yet.
I had a survey of my home and it was estimated at $30K with a 30% rebate from the government. It would take about 5 years to pay back the cost. I elected to go solar water heating instead. 2 panels with piping installed to an 80 gallon electric water heater with an internal heat exchanger. One small photo voltaic panel to run the pump. There is ethylene glycol inside the pipe and it circulates and heats the water. Works excellent. I live in Nor-Cal and we get a lot of sun. I need to comment on another statement that photo voltaic cells cost more energy to produce they generate. Maybe once but not true any longer. {Solar cells and energy payback In the 990s, when silicon cells were twice as thick, efficiencies 30% lower than today and lifetimes shorter, it may well have cost more energy to make a cell than it could generate in a lifetime. The energy payback time of a modern photovoltaic module is anywhere from to 20 years (usually under five)[9] depending on the type and where it is used (see net energy gain). This means solar cells can be net energy producers, meaning they generate more energy over their lifetime than the energy expended in producing them}
