People see big power companies ever increasing their costs. As energy cost go up for the long term, more people look for ways to use less energy to save money. People keep paying and paying the utility company and the bill gets higher and higher. With the cost of energy ever increasing to new highs, there are more people then ever looking into using alternative energy in their homes as a cost savings. The Mother Earth News article dated June 19, 2009 What Are the Pros and Cons of Going Off the Grid? by Linda Pinkham talks about the overall scope of going off the grid. Pinkham discusses some of the basic equipment advantages and drawbacks but didn't go into the true depth of the issues of costs versus benefits.
On May 21, 2009, Pinkham also wrote What’s the Average Cost to Install a Solar-Electric System to Power Your Home? The average home has an incoming electrical line of 240 Volts that delivers 100 Amps. Using Ohms law where Volts X Amps = Watts, the average home is capable of using up to 24,000 Watts (24 kW) of power. In Pinkham's article the installation and materials of a "10kW Gigantic" off grid system, less then half the average home's total capacity, would be over $100,000. He also lists a 5kW larger than average system costing $52,000.
When is it going to pay back?
Once a a good estimate of the cost for installation and materials is obtained, people want to know when it's going to pay off. Using the PVWatts Version 1 Calculator and, assuming a 7.9 ¢/kWh, from where I'm at in Minnesota a solar system installed would provide a cost savings of $406.22 worth of energy per year. Can that be right? With the $52,000 - 5kW larger than average system, it would take over 100 years to break even.
What isn't discussed in those articles is the lifespan of the extra electrical equipment that is needed to be off grid. Deep Cycle Batteries used in these systems have a limited lifespan. The most popular Deep Cycle AGM would have an average life of only four to eight years (http://www.windsun.com/Batteries/Battery_FAQ.htm#Lifespan%20of%20Batteries).
I have heard people who are interested in going off the grid say that their energy costs were too high. Those who are interested in going off the grid should start slowly by decreasing their energy consumption while on the grid. I think that it's good there are people like Ed Begley, Jr. out there that have their sustainable homes just to help the environment. At the same time, to go off the grid thinking that one would actually save money just doesn't make sense.
