A benefit to self generation is that the first watt of power you put into the Grid, is at the HIGHEST rate you are paying PGE. If you are on a TOU-time of use meter (peak and off peak) coupled with typically going into the 3rd and 4th tier on your bill, you could be paying as much as 64 cents a kilowatt. The watts your PV array pumps into the system start at the top rate!!!.. By cutting down on the 64 cent watts, you could be saving 8 times the money it costs you for the first watts you use.
Example: You save 1000 watts a month with your PV system. Your total use may be 2000 watts. The last 500 watts you use cost you 64 cents a watt and the next 500 watts about 45 cents. Combined, this results in a cost of $525. The first 500 watts you use and the second are at about 10 cents or $100. As you can see, by cutting 50% of your power use, you have lowered your bill by way more than half. It went from $625 to $100.
We have no choices with the tiered system. The more you use, the more it costs.
We do have a choice in the type of meter we choose. Flat rate, or time of use. (TOU)
TOU provides cheap power in the off peak times (peak is 11am to 7pm) IF you can control your usage to the off peak times, you will have a base rate of about 9 cents. The peak rate is about 35 cents. This means that your PV system will be pumping 35 cent power to your credit from 11 to 7 every day, and you will be using the power in the off peak times at 9 cents. You need a house with GOOD insulation, and exposure to benefit from the TOU system. If you can cool your house in the morning (to 11am) and it will hold the cool to 7pm. then this works great.
How to determine??? Do a simple test. Turn your AC to 70 in the morning and turn it off at 11AM. Note your inside temp. Check that temp at 7pm and see if you are OK with it. Yes.....go TOU. IF it is to hot, go flat rate.
Now for your needs:
Take a look at the last 12 months of bills, Total your KW usage. This is your annual KW usage.
Now look at the June through Oct bills. IF they are really most of the bill, then more considerations are needed.
Examine what your needs might be if you wanted to cut also your gas bills. An electric heat pump would heat your house instead of the gas furnace.. If you had a big enough solar system, it would provide both summer and winter for free. For simplicity sake, use the dollar to convert your gas dollars to electric and see how many more KW that would add.
Hot water is expensive!!! Solar hot water is the best bang for the buck. We recommend
www.solarroofs.com. We can provide and install this system for you. Check their web site.
Generally speaking, if you install a PV system that provides half to 3/4 of your total KW usage, your bill will drop drastically. IN Northern Calif, figure 5.5 hours a day for 365 days a year. A 1000watt or 1kw system will provide 5.5kw a day for 365 days or. 2000kw a year.
Click the
Solar System Costs link here for your next step.
