SFOG BLOG: Recent Comments

Comment on San Francisco Solar Maps

Robert — Fri, 12 Jun 2009 18:41:16 GMT

Response to a question: you may use the data on the website, provided you give proper credit. Links to commercial websites are not accepted.
Thanks.

Comment on San Francisco Solar Maps

Robert — Thu, 19 Mar 2009 00:15:44 GMT

After several emails from me over a year's time, the sf.solarmap finally gives different results for the different districts, 4.6 and 4.1 kWh per kW system per day for the examples in the previous posts.

It's still true, as I stated in my first post on this topic, that the actual output, kWh/kW system, is less than the input, kWh/m2. Also, the "Estimated solar PV potential" for each house on the sf.solarmap was increased earlier this year. In the case of my house, the new estimate is at least twice what is possible. So the results in the sf.solarmap are still too high.

Comment on San Francisco Solar Maps

Robert — Tue, 17 Mar 2009 04:42:04 GMT

Here are the current figures for the above addresses in the SF solar map:

11 Grove Street downtown (district 6, insolation 4.6 kWh/m2/day):
Estimated solar PV potential: 17 - 34 kW
Estimated electricity produced: 31025 - 62050 KWh/yr
Electricity produced (31,025 kWh/yr)/(17 kW) = 1,825 kWh per kW system per year, or 5 kWh per kW system per day.

2494 44th Ave. in the Sunset (district 4, insolation 4.1 kWh/m2/day):
Estimated solar PV potential: 7 - 13 kW
Estimated electricity produced: 12775 - 23725 KWh/yr
Electricity produced (12,775 kWh/yr)/(7 kW) = 1,825 kWh per kW system per year, or 5 kWh per kW system per day.

The results for output (5 kWh per kW system per day) continue to be the same in different parts of the city, despite the fact that the solar inputs are different.