A Report from the Solar Decathlon
Well, the Decathlon is underway, with 20 innovative teams fighting for victory as the best solar home to grace the Mall in Washington, DC. Today, the first event was judged. The Germans (Darmstadt) are leading the pack, with 209.206 points. Far, far behind them, in second place, is the University of Maryland (pictured) with 208.872 points. (e.g., 0.334 points separation out of a 1000 point contest). The Secretary of Energy visited a number of homes today, including that leading Darmstadt house.
So far, I’ve had the chance to visit eight of the houses and speak with team members from four others.
Okay, let’s make this clear, this is EcoGeek heaven. Extremely knowledgeable, enthusiastic, innovative people from universities around the world seeking to lay a path for a more sustainable future.
From new gadgets to applications of well known concepts, every house has something to excite EcoGeek readers. And we plan to share a few of those that got our attention with our fellow EcoGeeks.
First out of the gate, the University of Maryland’s LEAFHouse, in that distant second place (got it, that is a joke). First off, let me tell you that this is a magnificent home — wherever they end up in the actual competition, tip of the hat to a place that I would love to call my own. Beautiful, elegant, well-conceived, and highly energy efficient. But, well, one of the most striking elements of the house is now a decorative element that could become a mass market item in the years to come:
The Washington, DC, area is extremely humid in summer. Combined with the heat, Washingtonians often live from air-conditioned space to air-conditioned space for weeks at a time. Dehumidification of this space eats up much of the electrical cooling load — roughly about 30 percent. And, well, air conditioners are not necessarily the most efficient dehumidifiers.
The LEAFHouse team is using a Desiccant System, which has been applied to large structures but is not a player in the home market. The basic approach: use a desiccant (LEAFHouse: road salt, calcium chloride) to absorb water from the air and, when it is saturated, heat the water (with solar tubes) outside the building to evaporate out liquid to concentrate the desiccant again. Layman’s explanation: the desiccant is like a sponge, absorbing water; when it has too much water, it is shunted out of the building to be squeezed, to go back in and absorb some more water.
Inside the house, this looks like a waterfall in plexiglass. Thus, not only would it save on energy use, it also would calm residents. (Think of all those "waterfalls" on sale at your local housing goods store.)
And, well, there are next steps. In winter, the process could be reversed to humidify the air. And, in summer, the Liquid Desiccant Waterfall could contribute to cooling (the water absorbing some heat) and in winter, heating (evaporating from solar warmed water).
Now, to make it in the mass market, after they’ve worked through all the kinks, they will need a better name than Liquid Desiccant Waterfall to capture market share. But, for that, they might prefer someone from Madison Avenue over an EcoGeek.