A green White House

After the big send-off the day before yesterday for our Solar Road Trippers, I began to ponder what I would do if the White House was a building I was responsible for.

And, of course, the first thing I would do is not "put solar on it" but perform an energy audit.

It turns out that there has been at least one and possibly two serious energy audits done on the White House.

Our friends and partners Rocky Mountain Institute, together with the Department of Energy, the Lawrence Berkeley Lab and NREL did one for Bill Clinton in 1996, which resulted in a lot of retrofit work being undertaken to both the White House and the Old Executive Office Building. That report, titled "Greening the White House," is available, as is a summary here.

And, according to this news article here, the Obama administration ordered a new audit shortly after coming into possession of the First Mansion.

The next thing I would do is whatever the audit said were the "low hanging fruit," the most cost-effective and immediate energy saving actions. Given that the '96 audit aimed to pick most such fruit, we may be needing an apple ladder right about now, but that doesn't mean to say there wouldn't be some fruit to pick. Light bulbs, door seals, windows, attic and crawlspace insulation, insulation in general, and air leaks in general are all typical low hanging fruit (not in any particular order). The earlier report mentions that quite a few of these were done.

Then I might think about switching heat fuels. The White House needs a "hardened" system of utilities that can survive emergencies, and in particular must have seamless and uninterrupted electrical power, and so is ripe for a dedicated, microgrid combined heat and power system, or CHP.

I had only a short amount of time for research and couldn't find out what kind of system was currently in place. I would use natural gas, which is available by mains supply in DC, but I would keep a back-up supply in an underground tank. A natural gas CHP system can be up to 85% thermally efficient, which is much better than, for instance, an older oil-based heat-only system at 65%. And gas emits far less GHG per unit energy than oil.

Then, and only then, I might think about solar PV and solar thermal, or some other form of renewable energy. I'd put a fairly large solar PV system on one of the larger nearby buildings with less architectural and historical concern, or on the mall using trackers, and I'd put evacuated tube based solar hot water back on the West Wing roof, right where Jimmy Carter put his original system.

I might connect one of the original JC panels to this new system as a pre-heater, and just for sentimentality's sake. the LEED building system gives points for re-using and recycling materials, so you could pick up a LEED point for this.

Or put it one the grounds as a "statue."

President Carter said in his dedication speech that one day these particular flat plate collectors would perhaps be a museum piece, and they probably are. They were never more than 10% thermally efficient, even when they were brand new. They're very heavy, too, and so have a lot of embodied materials, glass, copper, aluminum, and steel.

I would guess that they capture about 100 to 200 watt-hours per hour of heat energy in the middle of the day, and much less at either end of the solar cycle. The new evacuated tube systems are much lighter, have fewer embodied materials, and are several times more efficient. they also start to work earlier in the morning and keep working later into the afternoon.

Ironically, however, you could do an audit and then do all the retrofit work and do it as well as it could possibly be done and still not succeed in drawing the public's attention to what you had done, or encourage others to do the same, while if you used one of the original Jimmy Carter panels, however inefficient they are, you might be able to get through to some folks.