Numbers in regard to solar panels, such as monthly savings, payback period, and others, depend on several factors. These include system size, placement in regard to the sun, location of the home, your energy lifestyle, and local electricity costs, among others. The only true way to determine your specific monthly savings is to have a site analysis performed by a local solar installer. There are also several online calculators that can give you a pretty good idea of monthly and long-term savings.

However, using some national averages, calculating the general difference in monthly electric bills incurred by an installed and functional solar PV system is actually quite easy. Let’s say you live on the temperate Pacific Coast, which includes Washington, Oregon, and California. According to the Department of Energy, the average household in this area pays about $63 per month for electricity. These numbers are for 2002, however, so, assuming a 7% increase in costs per year, that would put the average electricity bill in this region at roughly $108 per month in 2008.

So, assuming a 3 kW system is installed and there are roughly 6 hours of sunlight per day, we can then calculate the system output at 18 kilowatt-hours per day. That translates into roughly 540 kWh per month. After adjusting that number for cloudy or rainy days (decreasing it by 20 percent), we get a more realistic output of 432 kWh per month for the PV system. (more…)

Once your solar power system is up and running, your utility bill will certainly change. For one, you’ll see you total costs dropping. That’s the easy good part. But it is more complex than that and understanding your bill is important to maximizing your solar system’s benefits.

Baseline Usage and Peak Hours

If you already have a solar power system, then you have already spent some time getting to know your power bill BEFORE the solar system was installed. You should have a basic understanding of baseline usage and non-baseline usage charges and fees we all see on our electric bills. For those of you who have not take the arduous journey into your power bill, baseline usage is the amount of electricity (in kWh) that the utility company expects your household to use in a month. Non-baseline usage is billed at a higher rate and typically the higher you go beyond baseline usage the higher the electricity costs. Because baseline usage rates are lower than non-baseline rates, you can bet your utility is underestimating your expected power usage.

It is also important to note peak hour and off-peak hour rates. The difference between these two can be staggering. Peak hours are during the day and are higher in the summer when electricity is in peak demand and, coincidentally, when your solar power system is working at peak output.

Rates and other fees and charges will vary depending on your location and utility, as well your electric bill after an install. With the solar system installed, be aware that you may actually receive two bills if your gas and electricity is handled by the same company (such as PG&E on the West Coast).

A Second Bill?

The second bill is often called the Net Energy Metering (NEM) bill or will have a similar name. This bill will have your electricity production and consumption laid out next to each other on the page, thanks to the bidirectional meter installed with the solar system. Both categories will be tallied and your total bill will either be in the positive (money you owe) or negative (money or credit the utility owes you). (more…)

When excitement in an industry or movement grows, as we are seeing in the solar energy industry, it’s easy to lose track of the essentials, the building blocks. We get caught up in the latest round of funding, or the next promising innovation. Now, this is great stuff, with a potential to revolutionize the industry. But let’s not forget what is currently on our rooftops and, for the most, continues to be installed on our rooftops: ole fashioned, silicon-based, p-n junction solar panels. Despite the fact that the industry could conceivably take a massive turn in the near future, it is the understanding of current solar cells that will lead us into the next generation. That’s why today is review day. Because the question still persists: How do solar panels work?

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