The Pacific Northwest National Laboratory says coffee shops and fast-food joints can reduce their energy usage by 41 to 52 percent with upgrades to four areas of their restaurants:
- Ultra-efficient appliances
- Efficient lights reduce electricity usage inside and outside, and dimming controls can trim usage in the dining room
- Optimized heating, ventilation and air conditioning can be used to make better use of outdoor air and to recover lost heat
- Insulation: Cool roofs and high-performance window glazing will improve the “building envelope”
It would take between 1.5 and 3.5 years for the energy savings to pay for the cost of the upgrades, the report says. So, that’s great, right? But there’s a broader, ongoing debate over what happens to the savings after that. Will they just fuel more energy consumption somewhere else?
To do the fast-food energy calculation, PNNL researchers modeled a typical 2,500-square-foot quick-service restaurant and plugged it into a new U.S. Department of Energy simulation program called EnergyPlus.
Buildings account for more than 40 percent of the nation’s total energy use, and part of PNNL’s goal is to help reduce U.S. energy usage. DOE funds a Building Technologies Program to develop tools that will make buildings more energy efficient.
While energy efficiency is viewed as a worthy pursuit, there is an ongoing debate over whether it will ultimately reduce total energy use and help curb energy-related problems such as climate change. Some evidence shows people compensate for lower energy costs with more energy consumption.
A recent story in The Washington Post explained:
“Dishwashers use 45 percent less energy than they did two decades ago, according to industry data. Refrigerators use 51 percent less.
But on a per-capita basis, Americans still require about 70 million British thermal units a year to heat, cool and power their homes, just as they did in 1971. (One BTU is the energy required to heat one pound of water one degree Fahrenheit.)
A key reason, experts say, is that American homes are getting bigger, which means more space to heat and cool. And consumers are buying more and more power-sucking gadgets — meaning that kilowatts saved by dishwashers and refrigerators are often used up by flat-screen televisions, computers and digital video recorders.”
Dr. Harry Saunders of the University of Alberta explained this “rebound effect” in responding to a controversial story in The Economist about his research (There is also a response to that story from Evan Mills of the Lawrence Berkeley National Lab, who argues energy-efficient lighting is still worth the investment):
“Efficiency advocates sometimes dismiss rebound by only looking at ‘direct’ energy consumption – that is, consumption by households and for private transportation. Examples of rebound in this part of the energy economy would be driving your Prius more because gasoline costs you very little, or turning up the thermostat in your efficient home. But these ‘direct-use’ rebounds are small in comparison to ‘indirect-use’ rebounds in energy consumption. Globally, some two-thirds of all energy is consumed indirectly – in the energy used to produce goods and services. A residential washing machine may be energy efficient in terms of function, but in terms of production, the metal body alone requires energy to mine, smelt, stamp, coat, assemble and transport it to a dealer showroom and eventually a residential home. The energy embedded in your washing machine, or just about any product or service you consume, is very large. And remember that any money you save on your energy bills through efficient appliances or the like is re-spent on other goods and services, which each take energy to produce, all while more productive use of our money (e.g. in spending, savings and production) spurs a more robust economy, demanding even more energy.”
So, when it comes to our energy efficiency measures at home, fast-food restaurants and other buildings, maybe we need to super-size them?