Photovoltaic System Design
Designing a system that is right for you and your home requires careful consideration of many factors including budget, energy usage, insolation, product availability and space requirements. The following worksheets are for you to use as a guide. Bring the applicable completed worksheets to your consultation with us.
Grid-Tied System Design
1. Find your monthly average electricity usage from your electrical bill
This will be in kilowatt-hours (kwh). Because of air conditioning, heating and other seasonal usage, it is a good idea to look at several bills. You can add the typical summer, fall, winter and spring bills and divide by four to find the average monthly usage.
2. Find your daily average electricity use
Divide the monthly average number of kwh use by 30 (days).
3. Find your locations average peak sun hours per day
We use 3 hours as an average for New England’s year round average.
4. Calculate the system size (AC watts) to provide 100% of your electricity
Divide your daily average electricity use by the average sun hours per day. For example, if the daily average electricity use is 30 kwh, and the site is in New Hampshire, then the system size would be: 30 kwh/ 3h= 10 kw AC
5. Calculate the number of PV modules required for this system
Divide the system AC watts in step 4 by the CEC watt rating of the modules to be used, then divide by the inverter efficiency, usually 0.94 and you get the total number of modules required. (Round this number up)
发表于 2008-6-18 10:59:32
发表于 2008-6-18 22:08:43
