It’s crazy, but we know more about the efficiency of our cars than of our houses. Think about it, you probably know what kind of mileage your car gets but you unless you are especially geeky, it’s very likely that you don’t know how your home energy use compares to other homes in your community. You may be asking yourself why should I care?
Off the top of my head, here are three reasons to care:
1. A more energy-efficient home costs you less.
2. It’s good for the planet, really truly.
3. Energy efficient homes are more comfortable.
According to the most recent statistics from the Residential Energy Consumption Survey (RECS), the average annual energy expenditure across all types of residential structures in the U.S. is $1.03 per square foot. In a 2,000 square foot house, that is an average cost of $2,060. annually or $171 per month . That is much higher than it needs to be and it is possible to reduce the amount of energy used by 50% and more. Just a 50% reduction results in a potential energy savings of $1,030 annually. It’s money that you can park in savings for an early retirement, or you could just buy stuff. In any case, the interesting thing is that there is quite a bit of money to be saved just by improving the energy efficiency of your home.
If 97% of scientists agree that climate change is real, I’m jumping on that bandwagon. I don’t know about you, but it just seems wiser to be safe than sorry, especially when it comes to our precious planet. According to architecture 2030 buildings were responsible for 47.6% of the CO2 emissions in the US in 2010. The other two chunks were transportation at 33.4% and industry at 19.9%. Buildings are the biggest culprit, and while we need to tackle all three sectors, reducing CO2 emissions from buildings will have an immediate and significant impact. That is a sobering fact. It’s also a kick in the pants fact because we CAN build better buildings right now, and clearly we need to!
When buildings are built to improve energy efficiency, an often overlooked benefit is comfort. Not comfort as in luxurious spa kind of experience, but comfort as in thermal comfort, no need for long johns kind of experience. The factors that improve energy efficiency and comfort are better insulation, fewer leaks and fewer thermal bridges. Building this way takes extra attention on both the design and construction side, but it is certainly not rocket science, more than anything it is common sense and attention to detail.
If there was an MPG ratings for houses, it would be the The Home Energy Rating System or HERS, the most widely recognized rating system for home energy use in the US. HERS is overseen by RESNET, the Residential Energy Services Network. A building with a score of 100 is considered to be the average new standard home, the lower the HERS score the better the performance. The ultimate energy efficiency goal is a score of ZERO, which is a zero energy home, one that makes as much energy as it uses over the course of a year.
There are two paths to get to zero. Both are legitimate and have their place. For existing buildings, often the most practical method of getting to zero is to match the energy use over the course of a year with an equivalent amount of renewable energy sources such as photovoltaics or wind power.
The other path to zero is to limit the energy use of a building before adding the renewable energy source. This is most easily accomplished with new construction and high performance buildings with a HERS score of 50 and below are ideally suited to becoming zero energy buildings.
By using less energy, high performance buildings help limit the amount of CO2 in the atmosphere. As better buildings come online, older ones are demolished or they are improved. It is possible, according to architecture 2030 that we could have a significant impact on climate change if we all start to build better.
High performance buildings are the super bingo when it comes to money saved, good planet karma and comfort. We can build this way today, its a simple recipe that takes a little extra effort, but once you know how to build right, there is no going back!