Florida builders will have to cut the energy consumption of new houses by 20 percent in 2010, and by 50 percent in 2019 under legislation passed recently by the state’s Republican-controlled legislature and signed by Gov. Charlie Crist. The legislation follows on the heels of Crist’s executive order from last year, which already will toughen Florida’s Energy Efficiency Code for Building Construction by 15 percent compared with the 2007 code, effective Jan. 1, 2008.

With Florida’s strict new energy policy, Gov. Crist joins Gov. Arnold Schwarzenegger of California and other governors as states, rather than the feds, take the lead on addressing global climate change with aggressive action to reduce carbon emissions by promoting conservation and switching to green energy resources.

The new policy presents a challenge for Florida builders, who will have to figure out how to hit the state’s increasingly strict targets in the field. (As written, the 2007 Florida energy code is already 4 percent more stringent than the International Code Council’s model International Energy Conservation Code, according to a state-sponsored analysis.)

Jack Glenn, technical services director for the Florida Home Builders Association, says many of the state’s builders are already within striking distance of next year’s 15 percent home energy use reduction target.

Florida’s energy code is performance-based, Glenn explains; builders must use the state’s sophisticated EnergyGauge computer modeling program to project a planned home’s seasonal energy use and compare the bottom line with a baseline home built according to assumptions in the model. If the computer says that a proposed home will consume energy equal to or less than the baseline home, the building complies.

“If you have to score 100 to comply with the current code, then a 15 percent reduction would mean you have to reach a score of 85,” says Glenn. “At a 50 percent reduction, you would have to reach a 50. Well, a lot of our builders are currently in the range of probably 85 to 90. So it may just mean some minor adjustments in this first go-round, and the computer program allows them to trade off different elements of the building and to make their own determination as to what’s best for their customer.”

But a 50 percent reduction is another matter, says Glenn: “We have no idea how we’re going to accomplish that. It’s going to require some new technologies. It’s a goal, but I don’t think we can build an affordable house today, with today’s technologies, that can meet that 50 percent reduction.”

Phil Fairey, deputy director of the Florida Solar Energy Center, spearheaded the development of the state’s EnergyGauge software package and has been researching building performance with FSEC for decades. Fairey says there are numerous cost-effective ways builders can cut energy use well beyond next year’s 15 percent target, and the EnergyGauge software leaves builders flexible to work within their particular cost profiles.

“Anything and everything is allowed—there’s no prescriptive requirement. And if you wanted to, right now, you could go look and say, ‘What’s it going to take for me to get to 50?’ And no question about it, the number-one big hitter is, bring the ducts inside the conditioned space.”

Efficient windows are another simple option: “People have been complying with the code using single-glazed metal windows. But that’s going to be passé with the new targets, because the only way you’ll get there with those kind of windows is to use air conditioners with SEER ratings of 17.”

A minority of Florida builders who participate in the Building America program are already getting 30 percent or 40 percent improvement beyond code in some houses, Fairey says.

Florida’s new legislation closely tracks recommendations that Fairey made in a May 2007 report to the state Codes and Standards Office regarding the effectiveness of the state's energy code.

But Florida did not adopt one of Fairey’s potentially most high-impact recommendations: modifying the energy code and the EnergyGauge program to reflect building energy consumption for uses such as lighting and appliances, not just heating, cooling, and hot water.

In Florida, as well as nationwide, current code does not take these other energy drains into account. As a result, says Fairey, while heating, cooling, and water heating energy consumption has fallen dramatically in the U.S. since the 1970s, other uses have actually been increasing.“In Florida, heating, cooling, and hot water are a little bit less than 50 percent of total home energy use,” Fairey explains—so when the state aims to toughen the code by a certain percentage amount, “we’re really just talking about 15 percent or 20 percent or 50 percent of 50 percent.”

Into the category of “other,” he says, falls “everything else we do: refrigerators, televisions, washing machines, dishwashers, microwave ovens, stoves—you know, the works.”

New generations of plasma televisions, for instance, use more power than refrigerators do, he says—and they’re not regulated or even labeled. Says Fairey, “You can go a long way just with a label that says, ‘This model uses this much; that model uses that much.’” Of course, big appliances also add heat to the house, boosting the cooling load. “Basically, every kilowatt-hour that you put into the house ends up as heat that the air conditioner has to remove,” he observes.

If the code were broadened to include these power drains, Fairey says, existing appliance efficiency technologies, including items as basic as compact fluorescent bulbs, could bring a 50 percent total energy consumption cut in houses much closer to reality.

And Fairey says Florida’s new initiative is even more drastically limited by its exclusive focus on new construction. “It’s important to understand that if we only deal with new buildings, it’s going to take us 100 years to turn over the housing stock,” he says. “The real big prize is in the buildings that are already out there.” Potential energy savings from updating existing homes, Fairey argues, represents a larger and more affordable energy resource than fossil fuel resources like Florida’s offshore oil and gas reserves or the Midwest’s coal reserves.

But to exploit that resource, he says, the state would have to create incentives for companies to manage the house-by-house task of implementing conservation measures—and regulate the industry to make sure that those measures were applied effectively. “The likelihood that anything is going to happen without some kind of organized support from someone—government or anyone—is very small. But there is a huge potential for energy savings here. Just gigantic. Much bigger than the potential represented in this new legislation that is going to crank new buildings down to 50 percent by 2019.”

During Florida’s recent boom, Fairey observes, builders had scant incentive to pay attention to energy efficiency even in new construction. “They couldn’t get them out of the ground quick enough. People were buying homes before they were even finished and flipping them. There was no incentive to do anything except make money.”

But now that new construction has slowed to a crawl while energy prices have spiked dramatically, energy-efficiency retrofits may represent one of the few remaining business opportunities in construction. For contractors who are interested, the state’s EnergyGauge software offers an available design tool and a sales tool. “You can use the same code software we wrote to design upgrades for existing buildings and for doing Home Energy Rating Service [HERS] ratings,” Fairey says.”I encourage people to download it and play around with it for free, and look at what you can accomplish with it.”

Ted Cushman is a contributing editor to BUILDER magazine.