Feature

Putting Their Money Where Their Mouths Are: NASA Engineers Get Green
04.21.09
 
Green attic

In an effort to make his home more efficient, NASA engineer Steve Miller installed a radiant barrier in his attic. He spent about $250 on the work, which he did himself, and estimates that he saved $119 in the first summer alone. These photos illustrate how he installed the barrier. In the top photo, you can see how he cut an opening for the roof vents and left a margin of about 6 inches around the attic’s ridgeline for venting and circulation. The bottom photo shows how he left about 2 inches of clearance between the radiant barrier material and the insulation, and overlapped the rolls by about 6 inches. Credit: NASA

A few years ago, Stephen Miller and Mark Flahaut started taking a closer look at their electric bill.

Big deal, right? Who hasn’t been taking a closer look at their electricity bill over the last few years as gas prices rose? But what makes Miller and Flahaut different from most of the other people studying their electricity usage, is that they have prior experience in the subject.

“Energy is what we do here in our branch,” said Miller, an engineer in the thermal design branch of Johnson Space Center’s structural engineering division. “Where it goes and how it moves. So I decided to go off and figure out a way I can compare how my house is using energy.”

He was joined by another passive thermal engineer, Mark Flahaut, and before you know it, the branch had a competition on to see who could make their home the most energy efficient. Now, their closer look has spread to the entire engineering department.

“I think we’re starting to take a little bit of ownership of any sort of culture change because we do passive thermal control in our branch,” said Chris Madden, deputy chief of the thermal design branch. “That’s what we do for spacecraft, and we think we need to start being leaders in doing this for our everyday life.”

The aim, of course, is to see how much energy the team can save by actively trying to do so. Radical measures, Madden said, are encouraged. The thermal design branch team knows from experience that they work and can give you the hard data to back up the fact that they’re worth it.

In their quest to make their homes energy efficient, Miller has installed a radiant barrier in his attic, while Flahaut replaced his aging air conditioner, put in new thermally efficient windows and changed 40 of the incandescent light bulbs in his home out for the compact fluorescent version, in addition to installing his own radiant barrier and an additional 8 inches of insulation on his attic floor.

Miller spent about $250 on supplies for his radiant barrier – four rolls of barrier and one staple gun – and installed it himself over two days in December of 2005. The following summer, his electricity bill showed that he used about 6 percent fewer kilowatt hours than he had in previous summers, with a correction for the difference in average temperatures included in the calculation. Based on that, he determined that he saved $119 in that first summer, alone. By the next summer it was paid off, and last summer the difference was pure savings.

Flahaut put a bit more money into his changes. His home is smaller than Miller’s, so the radiant barrier only cost about $160. But because his home was old and there were problems with his ducts, he bought an entire new heating and cooling system, including an air conditioner, furnace and new duct work. The total cost was $9,000, but might have been more like $5,000 or $6,000 he’d been buying just an air conditioner.

The thermal windows added another $7,000 to his work. And the cost of the compact fluorescent light bulbs varies, but you can get a pack of six for about $20. That adds up to a hefty price tag, but so far he’s not regretting it. Since he began the improvements in July of 2005, he’s saved about $4,500 on his electricity bill.

› View graph to track the effects of each individual change (PDF 102 Kb)

Thermal windows

Among the many changes Mark Flahaut made to his home for the sake of energy efficiency, was the installation of thermal windows. Between that, a new heating and cooling system, a radiant barrier and compact fluorescent light bulbs, he’s saved about $4,500 on his electricity bill since 2005. Credit: NASA

The biggest change, Flahaut said, came from the new air conditioner, which, with his other changes, cut his energy usage from about 17,000 kilowatt hours per year to about 10,000. But if you’re looking for something smaller that still packs a punch, he suggested switching to compact fluorescent light bulbs. He did warn, however, that they weren’t perfect – he’s had to replace three so far, they’re not as bright as normal light bulbs and they contain mercury, which can mean serious problems if they break.

Obviously the financial savings are an attractive incentive in making such changes, but Flahaut, Miller and Madden all say that’s not the only reason they’ve made them. Doing their part to protect the environment is just as big a factor in their decisions.

“We, as Americans, consume the most energy on a per capita basis,” Flahaut said. “We have to do more to be responsible with our energy use. And we might as well save money in the process, too.”

But having improved their efficiency so much, they say it just gets harder from here. Flahaut and Miller have been using a device that will tell you how much current your appliances are drawing, in an effort to track down which things they should leave unplugged. And Madden is getting his children involved, as well.

“I made these plots for my house with a goal on it,” Madden said. “I printed it out, put it on the fridge and got the kids together and said, ‘Look, here’s what we’re doing.’ I thought they’d totally laugh at me and call me a dork like they always do. But they engaged. They kind of thought it was cool.”