01 Jun 2010

I turned 38 a bit over a week ago.  Also, I’m turning 20 million minutes old later this afternoon.  I discovered this while building a spreadsheet that calculates my family members’ ages in days, hours, minutes, etc.  It started out as a math thing with my 8 year olds.  I could make your eyes glaze over with when various people are turning certain days/hours/minutes old, so I’ll pass on that.  But it’s interesting to think about time and age in different units.

In other news, I’ve been appointed (pending receipt of the official notice) to my town’s Municipal Light Board, and a committee to figure out what to do with solar energy.  I’m excited for both of these posts, as I’ll learn a ton, and will have a chance to help our town be more sustainable, cost-effectively.  The solar project should be really interesting; the state solar incentive program has been tied up in a lawsuit which was just partially settled (at least the solar piece).  So, it’s time to roll.


Article 64

04 May 2010

My town, Concord, MA, passed Article 64 at this year’s Town Meeting!

That’s a big deal for me.  This article gives the Town Manager authorization to lease certain parcels of Town-owned land (the Ammendolia land and land around the sewage treatment plant) for 20+ years for a large-scale solar array.

There are a lot of open questions to be worked out, but it’s exciting to have the very real prospect of having a sizeable array here in town.

Here’s an article from the Concord Journal that was published before Town Meeting.  My guest commentary that appeared in the print version is not available online, alas.


09 Apr 2010

Whether has been either too horrific (major flooding!) or great (70’s in April!), same for work, to spend much time on this. So, here’s a quick update on our electricity use- pretty steady these days, our annualized consumption is 7260 kWh per year. Not bad for a family of six with electric stove and dryer.  Now that we have a pretty stable baseline, what should we do to shave it down?

Solar Schools

23 Mar 2010

I have no time for a blog post with any real content, so here instead are some links to other schools with solar:

There are, of course, many, many more out there.

And here’s what is thought to be the first net zero energy secondary school building in the U.S. (apart from old one room schoolhouses with no heat or electricity, I presume).

Solar Money

12 Mar 2010

The great state of Massachusetts announced a couple weeks ago that our town won a $150k grant from the state via the Energy Efficiency and Conservation Block Grant (EECBG) program from the U.S. Department of Energy (DOE).  The Town Committee that I serve on, CSEC,  is putting in another $100k, and our municipal utility, CMLP, is on the hook for $50k.  The RFP for a 44kW system is out and it looks like a lot of bids will be submitted.  The installation should occur this summer on Willard Elementary School, which is a pretty green school.

Details on the economics, etc., will follow.  As far as the Town is concerned, this is largely a windfall- the school system will get free electricity from the PV system, the CSEC money is from the Sawyer Funds dedicated to sustainable energy, and CMLP should recoup their investment through lower peak demand from the grid in the summer.

There’s a new 60 kW solar site at the local prison.

I’m interested in solar energy, data analysis, and visualization, so I downloaded some data (look for e.g. the CSV button here) for August 2009-January 2010 and popped it into Tableau.  The data starts in August because the system didn’t start running reliably until mid-July.  I choose Tableau because it allows me to dig into the data in some detail quite quickly.  And it makes nice graphs.  However, it’s not perfect; it’s expensive, closed-source, and has limited ability for statistical analysis.  R is better on all of these fronts (free, open source, great stats), but at the present moment I can work much faster in Tableau.

So, here’s what I found:

First, I looked at production by month.  I expected August to have more production than December.  So far, so good:

kWh by Month 2009-07 to 2010-01

The color of each bar is proportional to the height of the bar.  It doesn’t add any more information, so it’s kind of chart junk, but I think it accentuates the differences between months.

I was a little surprised by how low December was relative to July; to see what’s going on there (other than the days being shorter and the sun being lower in the sky), I looked at daily production:

Bar Graph of PV Production by Day 2009-07 to 2010-01I did the same thing with coloring here (except that I also grouped colors into 100-kWh buckets).  What’s interesting is that a good day in July resulted in over 400 kWh, while in December the best days netted 260 kWh or so.  That’s a 1.5:1 ratio, while the monthly ratios between July and December are more like 2.7:1.  The difference is clearly due to the number of bad days in each month- most days in August were good for at least 200 kWh, while there are a lot of dogs in December.  Some of these are due to cloudy conditions, while some are due to snow cover- the panels are close enough to the ground so that it takes a couple days of good sun before they melt enough snow to get going again.  It raises an interesting question of the cost/benefit of installing them a bit higher.  Without doing any analysis, I’m guessing the extra installation costs aren’t worth a few more days of mediocre production in the winter, but what do I know?

That’s all for now- the next post will show some basis analyses of this data.

Looking ahead

04 Jan 2010

I haven’t followed through with my “next up” items from my last post. I instead spent the last two weeks working relaxing, and spending time with my kids and wife, which was the right use of my time.

Here are a few thoughts for 2010:

  • I bought a few 2′ x 8′ x 2″ rigid insulation boards, which I intend to install in the crawl space underneath the room we refer to as “the cold bathroom”. The existing insulation, fiberglass batts, has largely come loose and is very ineffectual. This should be a relatively small, high-impact DIY insulation project (what’s worse than a cold tile floor in the morning?).
  • Recessed lights are dodgy. We have 3 recessed lights in a cathedral ceiling. They let a lot of heat through to the roof. When it snows, you can very quickly see where these fixtures are located from outside, due to the melting pattern. We use these lights (CFLs) minimally in the winter; the ambient heat in the room just flows right through the poorly insulated fixtures. In addition to wasting energy, this also promotes ice dam formation. Something must be done!
  • Massachusetts is launching a new solar incentive program. It is very complicated, but has the potential to keep solar rolling in MA- there’s more info at the mass.gov Solar Carve Out page.