Energy Efficiency: Homes Bigger Worry Than Cars

Plugging the energy drain in energy inefficient homes, before targeting vehicular gas emissions, may be a more environmentally responsible thing to do. This post from Los Angeles Times discusses how identifying and retrofitting old, energy inefficient homes can go a long way in making Los Angeles greener.

Many of us living here in Los Angeles try our best to be as environmentally responsible as possible. It’s a difficult task, because, until recently, we’ve essentially been operating blind when it comes to information on one of the biggest energy users in our lives: buildings.

Buildings emit nearly 40% of the greenhouse gases in Los Angeles County due to electricity and natural gas use. Yet, perhaps unsurprisingly in traffic-besieged L.A., we have primarily focused on reducing vehicle greenhouse gas emissions instead. Despite our good intentions, this is a somewhat limited strategy. Most of us replace our cars every 10 years or so, taking older, inefficient models out of service. Most of our housing stock, on the other hand, was built between 1948 and 1964—much of it energy inefficient.

When it comes to our housing, old and inefficient tends to stay old and inefficient.

Buildings don’t come with energy use tags, like cars do. So how do you know if you live in a Prius building or a Hummer building?

One way of determining a building’s efficiency is by comparing its electricity and natural gas consumption to that of other buildings, indexing by age, size, and use. But because California protects individual customer energy billing data in the name of privacy, it’s nearly impossible to make building-by building comparisons.

This information deficit comes despite statewide regulatory pressure to improve performance. California’s Clean Energy and Pollution Reduction Act of 2015 calls for a doubling of building energy efficiency by 2030. The state’s ratepayers have already invested nearly $13 billion in building energy conservation measures since energy deregulation in 2002.

It’s well known that conservation is the most cost-effective way to reduce energy use—but data are the key. Instead we’re spending billions of dollars with little idea of our baseline use.

Thankfully, we here in Los Angeles have a new tool to help. Last month UCLA’s Institute of the Environment and Sustainability (where I’m a professor in residence), debuted a new instrument called the Energy Atlas. Using address-level electricity and natural gas billing data – aggregated to protect customer privacy— the Atlas reveals energy use and greenhouse gas emissions of buildings sorted by different characteristics like the wealth of the owner/inhabitant.

At first glance, the Atlas’ findings seem obvious. Malibu residents, with their massive homes, are the biggest energy users in the Southland—averaging 95.28 BTU per capita. (A BTU is the amount of energy it takes to heat a pound of water by one degree Fahrenheit.) Compton residents, on the other hand, only use 16.28 BTU per capita.

Here, however, is where things get interesting.

The highest BTU consumption per square foot for single-family dwellings is in Compton. One of the lowest is Malibu. Per square foot, Malibu homes use 43,637 BTU while those in Compton use 54,134 BTU.

These data are particularly startling if you survey the neighborhoods in question. Drive around much of South L.A., for example, and you’ll see many houses with no air conditioning, no ceiling fans, certainly no solar collectors. Just small hot houses in the summer, and cold ones in the winter that still use a great deal of energy.

This is generally true of other neighborhoods across the city. Older buildings in low-income neighborhoods use for more energy per square foot than newer buildings along the coast. The difference is due to the implementation of Title 24 in 1978, which requires energy conservation measures in new construction: insulation, window efficiency, heating and air-conditioning efficiencies and so forth. It shows the importance of good building codes.

That said, older buildings still compose the majority of our housing stock. So if the goal is to make L.A. a greener, more energy-efficient place, funds need to be directed toward older, high energy-use buildings.

Using the Atlas, we can identify these neighborhoods and prioritize them for energy efficiency programs. That’s not happening. Instead, individual customers apply for conservation programs through their utility—regardless of how efficient or inefficient their home is. Billions are being spent blindly as a result.

If we change our tack and use targeted, specific data to retrofit older, inefficient homes, it will enable us to reduce greenhouse gas emissions, meet statewide goals and improve the quality of life of residents in some of L.A. County’s most underserved communities.

Source: Creating a green Los Angeles needs to start with our buildings, not our cars – LA Times