Russell's Blog

New. Improved. Stays crunchy in milk.

First day of solar production

Posted by Russell on June 04, 2008 at 12:56 a.m.
The contractors installed the last row of panels this morning and switched on our solar array. Our house now produces about 15% more electricity than it uses!

The array produces between one and three kilowatt-hours for every hour of sunlight, so for today's half-day of production, we've generated 13 kwh.

Here's the read-out on the inverter :

Sadly, I don't have a way of getting the data out of the inverter yet. Once I add the RS-232 module, I'll have have more interesting things to say about our system. I'll post some pictures of the array itself once we've passed inspection.

The Sunny Boy inverter has an interesting user interface. There aren't any buttons -- you interact with the display by knocking on the front panel with your knuckle.

Make it stop, make it stop!

Posted by Russell on June 02, 2008 at 5:26 p.m.
A friendly reminder to those who are following the nomination process: Party primaries are not national elections. Political parties are essentially private clubs. Subject to a few basic limitations (e.g., Brown v. Board of Education), they can make up whatever rules they like. If the Democratic Party wants to select the presidential nominee via a dance-off, or a hip-hop battle, or an egg toss, that is perfectly legal.

I keep reading about how the party isn't allowed to take away Florida and Michigan's delegates. Of course they can; it's a private club. In fact, their rules stipulate that they must strip the delegates in this circumstance.

It's obvious to everyone that the nomination process isn't perfectly equitable, but the system we have now is a huge improvement over the smoke-filled-room method of the very recent past. Hillary Clinton has raised some important objections to how the system works. That's good. It needs improvement. However, winning the nomination and fixing the nominating system should not be conflated. This is her party, after all. She's been extremely influential in the party for almost sixteen years. If she wants to advocate for reforming the process, then she was welcome to spend some of those sixteen years of influence, you know, influencing. After the election is over, if she uses her influence to push for reform, that would be a great service to the party and to the nation. But pushing for reform in order to win isn't good for anyone.

I should point out that the general election system isn't exactly perfect either. Any competent candidate must demonstrate the technical abilities needed to campaign and win, fair and square, even in a system that is unfair and warped. I should also add that the Democratic nomination process and the general election process closely approximate a fair and equitable system, to a precision of a percent or thereabouts.

Elections are political instrumentation. They measure the prefrences of large groups of people. Say, for example, that you take a measurement with a volt meter. It reads 5.13V, plus or minus 0.5%. It's not acceptable to write down 5.17V because you think the probe contacts are a little dirty, and that's throwing off the measurement. However good your intuition and experience, that's called fudging your numbers. If doesn't change the results, then a little fudging won't do much harm, even if it is bad methodology. If it does change the results, then it's fraud. Bad scientist. No tenure.

Solarizing!

Posted by Russell on June 01, 2008 at 9:37 a.m.
Our contractor, EE Solar, is about halfway finished with the solar installation at our house. Here is what they are installing :
  • 14 SunPower 230 watt panels
  • One SMA Sunny Boy 3000 inverter
  • A second digital utility meter
  • AC and DC disconnects with lockout-tagout switches.
The 14 panels will be arranged into two arrays with south-facing exposures producing 3220 watts of DC power. The inverter is about 95% efficient, so the nameplate capacity will be 2854 watts. The USGS indicates that we should get about seven to eight hours of usable sunlight per day on average. The array should produce an average of 17 to 20 kilowatt hours a day. This should easily cancel out our usage, and maybe a little beyond. I'm hoping for slightly better production, since Pasadena is higher and dryer than most of the LA basin.

Here is the equipment after delivery and upacking :

We were supposed to get a Sunny Beam monitoring station, but evidently there are some issues with buggy firmware, so they won't be available until September (more about that later).

So far, roof has been preped, the mounting rails are installed, the conduits are bolted in place, the DC wires are pulled, and the inverter has been bolted down. All that's left is to hang the panels, do the AC wiring, and get the inspection.

The installer crew was supposed to finish that on Friday, but evidently they decided to take the day off. The project manager at EE Solar pitched a fit. Nick, the crew boss, called on Friday to say he was really sorry. I told him that his schedule is his business, but if he can't come when he promised, he ought to let us know. On Moday, I'll ask him to run some extra conduit for ethernet to make amends.