Tuesday, January 19, 2010

QA3

Q
Hi guys,
Congratulations on your startup. Interesting monitoring site with neat data presentation.
What do you estimate the annual kwh production of this array ?? Take care
Thanks

A
We asked for a system that would produce what we were currently using. We forwarded utility records to our installer and he told us this was the size system we would need. I went back in the blog to look at records and for the previous year we used 7984 kwh, 665/month, or 21.87 per day on average. So that is what we expect to produce over the course of the year.

Discussion
We expect more light in the summer but the panels will be less efficient due to warmer temperatures. So as time goes on we hope to see increased production just at lower numbers. Our panels are 215 watt rated, so that would be the maximum number we could see on the monitoring site. For efficiency sake, if we see 188, that means that panel is converting 87% of maximum. We also expect we are using more energy with the garage addition.

The reason we went with this size system rather than the breakeven point that a smaller system offered was we wanted to be able to convert to net metering without any subsidy like payout down the road and still make all we need. With selling the renewable energy credits we will make an extra seven cents per kwh, not sure how long this will stay around.

No comments:

Post a Comment