Addressing climate change requires two approaches – mitigation of emissions, and adaptation to its impacts. In this PechaKucha presentation presented as part of the American Association for the Advancement of Science’s Visualizing Science Policy 20×20 event, I lay out the case for how buildings are a critical – if sometimes forgotten – part of the solution. I invite you to watch this talk on YouTube, or read the transcript below.
Last September during Hurricane Irma, a tree branch hit a transformer and knocked out power to the air conditioning system of a nursing home in Hollywood, Florida. There were portable air conditioners on site, but they were insufficient, and temperatures rose to a sweltering 110 degrees Fahrenheit. By time emergency responders realized the scope of the problem, 12 residents had tragically lost their lives.
It was situations like these that compelled me a few years ago to set aside my career as an astrophysicist and devote my attention towards the phenomenon that’s making extreme events like Hurricane Irma more intense – and that’s climate change.
Through this AAAS Fellowship I’ve had the privilege of working with the Department of Energy’s Building Technologies Office. And when I told people I’d be going to BTO they’d say…”Why? I thought you were concerned about climate change.” And I’d have to tell them that in United States buildings consume about 40% of all energy and 75% of all electricity. So if BTO could achieve its mission of making building technologies more energy efficient, not only could we create jobs and save tens of billions a dollars a year for Americans, we could also cut out a significant chunk of our greenhouse gas emissions, and begin to mitigate this massive problem.
So I’m going to put my salesman’s hat on for a second and sell you on two energy efficiency success stories. Number 1! This [pointing towards slide] is what refrigerators used to look like – bulky, ugly, expensive energy hogs. But through advances in technology refrigerators have more available space, yet only consume 1/4 the energy, cost 1/3 the price, and allow you to watch cable news right on the refrigerator door!
Number 2! Clothes dryers, which consume about 1% of energy in the U.S., largely by heating and evaporating water. But right now researchers at Oak Ridge National Laboratory are working on ultrasonic drying technology in which a rapidly vibrating membrane atomizes the water, which can then be siphoned off as a cool mist. If we can bring this to scale you will be able to dry your clothes in half the time with 1/5 the energy. And I’ve already got the slogan: The Ultrasonic Clothes Dryer – Taking your sock drawer, to Mach 4.
But mitigating emissions goes beyond just using less energy. It’s about using the right kind of energy. Every so often I’ll run into a young idealist who will say, “We need to go 100% renewable energy! More wind! More solar!” Our electric grid must balance generation and demand in real time. And while admire the idealism, how do we meet demand when the sun stops shining and the wind stops blowing?
There is a new device that’s made its way into about half of all buildings, and that number is rising. That device is the smart electricity meter. And what’s unique about it is that it enables utilities to send signals to buildings.
I want you to imagine the hottest day of the year. People are getting off work, driving home, and what’s one of the first things they do when they walk in the door? They turn on their air conditioners at the same time. These tend to be the highest demand hours of the year, and the grid has to be overbuilt to accommodate them. It would be like building a 100-lane highway just to accommodate Thanksgiving Day traffic. It’s great for a few hours per year, but then we have to pay to build and maintain all that infrastructure that most of the time is being underutilized. And the more lanes of the highway we drive on, the higher the toll – or in this case the price of electricity – gets for everybody.
Now smart meters allow utilities to send signals to buildings that are like, “Hey, we’re about to have a really expensive event on our hands. If you are willing, we will pay you to reduce your demand.” And literally with the instantaneous flip of a switch, buildings help the grid balance, including instances when variable renewable energy like solar and wind suddenly become unavailable. This is known as demand response.
Another way to help the grid balance is by storing excess solar and wind energy, then dispatching it later as needed. Yet going 100% renewable requires a ginormous amount of storage. We can get some of it from grid-scale pumped hydroelectric energy, and some of it from electrochemical batteries.
But there’s another way to store energy – in a building’s thermal mass. So imagine that you take a liquid material and embed it in the bricks that make up the wall of your building. It’s a hot, sunny day, so using available solar energy, the grid instructs your building to turn on its air conditioning at 2pm. The liquid material freezes, and AC shuts off at 5pm. The building then acts like a giant cooler, keeping the occupant comfortable without having to consume electricity at the worst part of the day.
And while all of this is fantastic, even if we could go zero carbon tomorrow, so much inertia has been built up in Earth’s system that global climate conditions would continue to deteriorate for decades to come. That means more extreme weather events, and more prolonged power outages.
Now it would be great if everyone could evacuate to safe locations, but for a variety of reasons that remains impractical or impossible for far too many people. That means we need ways to help people shelter-in-place safely. And if you need buildings to maintain safe thermal conditions longer and with less energy, two of the most valuable assets are high-quality walls and windows. Combine that with network connectivity and smarter controls, buildings will eventually be able to prepare themselves thermally and electrically when adverse conditions can be predicted ahead of time. And unlike centralized power plants or even solar panels, energy efficiency and demand response can be deployed absolutely anywhere.
Now look, I fully acknowledge that there are other resiliency strategies out there. Utilities must continue to harden our electrical distribution system, and communities should have up-to-date climate and disaster preparedness plans. But as long as climate change remains a wicked problem, everyone one of us, in our own capacities, is going to have to do what we can. Then maybe, collectively, we’ll get to the point where tragedies like the one in that Hollywood, Florida nursing home never have to happen again.