We’ve received a few emails regarding solar energy.

Off grid vs net metered?

Producing our power means having the potential to be more energy independent while still being able to use the grid for backup. With utility “net metering” we get a bill from the power company only once a year. This allows us to “run the meter backwards” during the summer, and then use that excess power we have accumulated for use in the evenings and at other times when the sun is not shining. Over the course of a year, all our production and usages are averaged. We pay only for the “net usage.” With grid-tied net metering we have the best of both worlds. These systems are more efficient and less expensive than systems that use batteries for backup power. However, remote property owners have found that it pays to be “off the grid” because of the savings resulting from the cost of land away from the grid are considerable.

What kind of system would I need?

Some points you may want to consider in deciding about a solar pv system before you contact a solar company (or DIY).

1. Do you have a south facing section (rooftop or arbor) that receives adequate sunlight, i.e., no nearby trees or building that would shade the area?

2. Check with your utility company to see what system is allowed: i.e. “off the grid” or “grid tied.”? Or what can you afford?

3. Check your utility bills. How much electricity do you use on an average per year. Before we got energy efficient appliances we were using an average of 10.6 KW per day, presently we are using 6.5 KW on average.

4. Choose solar panels to fit your needs. We chose Sharp 165 W(12 panels). California Energy Commission has rated all makes of solar panels by independent testing to help assist people. No solar panel puts out as much as it claims. Therefore, the Sharp 165 W was rated as 144.8 W (not as the manufacturer stated 165 W per panel) but still very good). Multiply that by the number of panels you plan to buy. Therefore, we get 1727.6 W from them under optimal conditions (144.8 times 12 panels in our case). As for a SMA inverter, we purchased a 1800 Sunny Boy. If you want your PV system to store excess in batteries, you would have purchase a Sunny Boy 2500.

5.“How much PV you need depends on your power loads and their duty cycles. If you want to completely replace your current electrical purchases from the utility with a PV system, you could look at your kWh usage on your electric bills for a year, calculate a daily average, and divide that by the number of average daily sun hours for your location. For example: 3600 kWh/yr divided by 365 days/yr equals approximately 10 kWh/day, divided by 5 sun-hours per day (for locations in middle America), equals 2 kW. This would indicate that a 2-kW system would, over the course of an average year, produce enough energy to replace the power you are currently using.”read more >>

In addition, besides solar panels that are placed on roofs there are available models that are freestanding units and quite inexpensive.

How much KW does your system produce?

Our solar array photovoltaic system consists of 12 Sharp 165 panels and a 1800 Sunny Boy Inverter. The 12 panel system should, on a prime day, produce approximately 7.2 KW. Since installing our system in late November, on a sunny winter’s day the system produces approximately 4.2 KW.

What happens if you exceed the KW amount ?

The city of Pasadena is also offering its residents a chance to switch any grid energy sources to “Green Power.” Taking advantage of this means that any additional energy that our household uses will now be from a green source.

Weather Report: Going to be a crisp sunny day.

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