Is Energy Saving Weatherization Being Wasted in Florida?
Porches. Trees. Shade. Big Windows. Thomas Edison didn't need no weatherization.
One should never be surprised to see politics trump logic every time, but Brian's post $5 Billion in Stimulus Cash to Help US Cut Back on the A/C was so depressing. He quotes the New York Times:
An unusually large share of the money will be spent not on keeping cold air out but on keeping cold air in. As a result of a political compromise with Sun Belt lawmakers last decade, the enormous expansion of the weatherization program will....help states in hot climates, like Florida, save on air-conditioning.
But that is backwards; in hot climates you don't want to keep the cold air in, you want to keep the hot air out.
New York Times
Here is Robin Dias, "weatherization coordinator" looking for leaks with a blower test, the accepted technology. It works wonders up north for determining the leakage of a house. Too much leaking out? Go caulk every opening and sill and seal the place tight. It will definitely reduce electric bills and make it cheaper to keep the house cool. Of course there is a side-effect of sealing oneself into the house; unless fresh air is brought in, one can get a toxic buildup of volatile organic compounds, formaldehyde and other undesirables. Are they spending the money on an enthalpy recovery ventilator every time they seal a house up?
Furthermore, personal behaviour appears to be different when weatherizing for hot climates; A Texas study linked to in the Times found that when people got better air conditioning they used more of it, keeping it on longer and at a lower setting on the thermostat. It is Jevons Paradox in action: cheaper supply and greater efficiency leads to greater consumption.
This is how they used to do it in Fort Myers before air conditioning; stilts kept you above floods, bugs, and helped catch breezes. It's not too terrific in hurricanes, but there are other things that could be done:
Houses in Bermuda with white roofs. Source: Green Owl
Paint the Roof White.
That is what Energy Secretary Stephen Chu says:
Painting flat roofs of homes and commercial buildings white would reflect more of the sun’s heat back to space and reduce electricity used for air conditioning by as much as 15 percent, Chu told reporters today in London.
Read more in Brian's post White Roofs to Sweep the World, Fight Climate Change
The New York Times talks about putting reflective film on the windows, but when you open the windows it doesn't do any good. An awning lets you get natural ventilation and still keep out the sun. More on Awnings: Time to Bring Them Back
Low-tech Tips: Keep Cool with Awnings
Edison House, Fort Myers
Put on Porches
Thomas Edison never went to Fort Myers in summer, almost nobody did. But when he did go, he was protected from the sun by a deep porch that both shaded people and kept the house cooler. The windows were big and the ceilings were high to maximize natural ventilation.
Lloyd Alter, deck in Toronto
Plant a Tree
OK, that isn't Florida, it is the view from my window, but the principle is the same: shade your house with a tree. You get a double benefit, as a California study showed:
"Trees provide a cooling bonus. To keep themselves cool, trees pump water from the ground into their leaves. As this water evaporates from the surface of the leaves, it cools the tree. This "evaporative cooling" cools the surrounding area, too."
They used to get this in Florida; Flint Hall at the University of Florida used to be covered with them. As I wrote in Planet Green:
With the new weatherization grants, the salesmen are out peddling ground source heat pumps to keep you cool for less, but really, free is better.
Climbers can dramatically reduce the maximum temperatures of a building by shading walls from the sun, the daily temperature fluctuation being reduced by as much as 50%.Together with the insulation effect, temperature fluctuations at the wall surface can be reduced from between –10°/14°F to 60°C/140°F to between 5°C/41°F and 30°/86°F. Vines also cool your home through envirotranspiration.
More in Low-tech Tips: Plant Vines
Realistically, there is no way that one is going to live through a summer in much of Florida without air conditioning. But when throwing around weatherization money, is it not reasonable to throw it at things that reduce the air conditioning season and keep the heat out, rather than sealing it all up to keep the cold in? The goal should be to fix the houses to use as little air conditioning as possible, not just make it more efficient. Figure out how to make it easier to live without air conditioning instead of subsidizing the increased use of it. It is just backwards.
12 Big Steps to Make Building Better
More low-tech tips that can help avoid air conditioning:
Low-Tech Tips: Tune Your Windows
Low-tech Tips: Get the Roof Overhangs Right
Get a Heat Recovery Ventilator if You Seal Your House Up Tight