TIL about the electric grid
The electric grid are networks that carry electricity from central power plants to our homes. But how exactly is electricity generated and brought to our door? And what needs to change if we’re going to transition to generating “clean” electricity? In this episode of TILclimate (Today I Learned: Climate), Harvey Michaels, lecturer at the MIT Sloan School of Management, joins host Laur Hesse Fisher to explain the history and perhaps surprising features of the electric grid, and what changes are in store for the future.
This episode launches a new season of TILclimate that will explain our global energy system, its relationship to climate change, and what our options are for keeping the lights on while creating a clean energy future. For this season, TILclimate is partnering with the MIT Energy Initiative, which will air longer interviews with each guest to take a deeper dive into these topics.
Harvey Michaels, an MIT alumnus now lecturing at the MIT Sloan School of Management, researches energy management and efficiency and smart-grid-related opportunities to mitigate climate change. He is a member of Future of the Grid at the MIT Energy Initiative, Efficiency Forward at the Sloan Sustainability Initiative, and Project Faculty for Energy Democracy at the MIT Media Lab. Prior to joining MIT, Harvey Michaels worked at energy efficiency companies Xenergy and Aclara Software.
For more episodes of TILclimate, visit: tilclimate.mit.edu
To listen to the MIT Energy Initiative podcast, visit: energy.mit.edu/podcast
For in-depth analyses on energy technologies, check out the MIT Energy’s “Future of” report series: energy.mit.edu/research-type/future-of/
- Laur Hesse Fisher, Host and Producer
- David Lishansky, Editor and Producer
- Rachel Fritts, Graduate Student Writer
- Olivia Burek, Student Production Assistant
- Music by Blue Dot Sessions
- Artwork by Aaron Krol
Produced by the MIT Environmental Solutions Initiative at the Massachusetts Institute of Technology
Laur Hesse Fisher: [00:00:00] Hello and welcome back to TIL Climate, the show where you learn about climate change from real experts. I’m your host Laur Hesse Fisher, from the MIT Environmental Solutions Initiative, in lovely Cambridge, MA.
Energy is the lifeblood of our society. It fuels the production of our food, and things we use every day, and powers our homes, cars, and workplaces. The cost of energy impacts the price of pretty much everything. A world without the cheap and abundant energy that we have today, well, we wouldn’t recognize it.
And yet, generating energy for electricity and heat is our society’s number one source of greenhouse gas emissions. And as those emissions cause global temperatures to rise, coastlines to recede, and natural disasters like wildfires, floods, and hurricanes to intensify… well, the world we’re creating is one we won’t recognize either.
So, in this second season, we’ll be looking closer at how energy is generated and used, and what options we have for keeping the lights on without continuing to emit dangerous levels of CO2. Sometimes this is called “decarbonizing” our energy. We’ll speak with experts who’ll answer questions like, how do fossil fuels like coal, oil, and natural gas compare to each other… and to other non-fossil fuel energy like wind, solar, and nuclear? Is it really possible to capture and store CO2 from power plants? What is fusion and will it really solve all of our energy problems? And why are solutions that sound straight-forward, like replacing fossil fuel plants with solar panels and wind farms, actually a lot more complicated in reality?
We’ll answer these questions and more. To produce this season, we’re partnering with the MIT Energy Initiative who is doing a set of companion episodes. Check out their podcast for longer-form interviews with our same guests. You can find the link in our show notes or search for “MIT Energy Podcast.”
OK, let’s get started. In this season’s first episode, we’re going begin at the beginning: with the electric grid, which are networks that bring most of us our electricity. We’ll explore how it was built, how it works, and the challenges we need to overcome to decarbonize our energy.
We sat down with Harvey Michaels, a senior lecturer in the MIT Sloan School of Management.
Harvey Michaels: [00:02:39] My focus area is energy management which deals with the wise use of energy, energy efficiency, smart grid and related opportunities to mitigate climate change.
Laur Hesse Fisher: [00:02:50] But let’s start at the beginning. At the dawn of the electric age.
Harvey Michaels: [00:02:54] most people rate the creation of the electric power grid as probably the number one thing that happens in the 20th century.
So electricity is a very intriguing and complex technology that became something really important when Thomas Edison made the lightbulb. And once he had that, he had to invent an electric utility so that people would have electricity to run these light bulbs.
Laur Hesse Fisher: [00:03:21] In 1884, he opened Pearl Street Station in Manhattan, NY. This was the first-ever commercial power plant. Over time, more and more people wanted in on the action and more power plants started appearing across the country.
Harvey Michaels: [00:03:35] This powered major cities the United States, but it wasn't really until the Great Depression in the 1930s under a part of the New Deal to create power plants for rural America. And by the time the Depression was over at the end of the 1930s pretty much everybody in the United States had power.
We would build larger and larger electric power plants, and these were powered either by burning fossil fuels-- oil, gas, coal -- and using those to create steam in a boiler and the boiler steam would turn a generator -- an electric turbine -- and in the process would create the flow of electrons.
Laur Hesse Fisher: [00:04:20] Right: fossil fuels are really good at producing steam and this steam is used to push a turbine. It’s the movement of the turbine that then generates the electricity, and helps send it to our homes.
Harvey Michaels: [00:04:32] So a generator is really a spinning magnet that is pumping electrons into the wires and it's creating this flow of electrons that goes first into very high voltage wires, which are called transmission lines. And then it goes to a more local distribution network where it steps down in transformers to lower voltage and flows through the city streets or in the local neighborhood wires to people's homes.
Laur Hesse Fisher: [00:05:11] That might all sound very obvious; you probably see these wires every day. But there is a fascinating feature of our electric grid that most people don’t think about -- and it’s incredibly important when we’re talking about energy and climate change.
Harvey Michaels: [00:05:26] The complexity of the grid is that there needs to be exactly the right amount of power put into the wires to serve all the instantaneous needs of all the people on the system. It doesn't really have the ability to store electricity in the wires themselves. So the electric company has to create a system so the amount of power that's being injected into the wires is just about exactly equal to the amount of electricity that's being taken out of the wires.
If it has too many electrons in the wires it can essentially pump them into the ground. But it's wasted at that point. So the idea is to have it just about right.
Laur Hesse Fisher: [00:06:12] But if there is too little energy in the wires to keep up with demand, people lose power. We have traditionally dealt with this problem by having two kinds of power plants: the kind that supplies most of our energy needs, and the kind that can be easily turned on -- or dispatched -- when energy demand suddenly gets high.
Harvey Michaels: [00:06:31] Some of the larger plants that run on fossil fuels like coal take several hours to start up or to turn off. So the tendency is to run them pretty smoothly over a long period of time. Those kind of power plants are called base load plants.
Laur Hesse Fisher: [00:06:49] Baseload plants are great for making sure that there’s some energy available at all times.
Harvey Michaels: [00:06:55] since the amount of electricity modulates so much depending on the time of day and the weather you need to have some power plants which are easy to turn on and turn off.
Laur Hesse Fisher: [00:07:08] We need dispatchable plants to pick up the slack for these high-intensity periods. And for the most part, in the US, these dispatchable power plants run on natural gas.
Harvey Michaels: [00:07:20] And a natural gas plant can be turned on quickly and produce a lot of electricity quickly. It's a pretty expensive power plant to run: it costs more to make a kilowatt hour with a gas turbine. But you need it because we need to balance the system.
Laur Hesse Fisher: [00:07:37] So using less energy during these high intensity periods -- like the early evening when a lot of people come home from work -- can be one way to help decrease these peaks and avoid needing to turn on these dispatchable plants.
The thing is, the fastest-growing sources of low-carbon energy -- wind and solar -- kind of disrupt this balance because they don’t always add electricity to the grid at the exact time we need it. We have less control over it.
Harvey Michaels: [00:08:05] And when you have a confluence of events where there isn't any wind blowing and the sun isn't out and there's a really strong draw for electricity then you need the system to still be able to work which means you need to have a lot of safety built into it.
Laur Hesse Fisher: [00:08:25] This is a big deal when talking about how to add more wind and solar energy to the grid and yet still making sure there’s enough energy for everyone. There are ways of dealing with this and we’re going to have an entire episode on this issue of what’s called intermittent power, and batteries and storage, so stay tuned. We’re also going to have an episode on nuclear power, which is a low-carbon source of baseload power.
For now, we haven’t talked about two other major uses of energy: heat and transportation. But they are super relevant to discussing the future of our electric grid. We’re really dependent on using natural gas to heat our buildings and oil to power our vehicles. And so a lot of the conversation among energy experts on how to lower emissions from heat and transportation -- is to electrify them.
Harvey Michaels: [00:09:18] To stop climate change we need to both make our electric grid mostly carbon free and make our buildings mostly electric. And to do that we need to switch off of using gas for heat and hot water. We need to stop using as much gasoline for automobiles and use more electricity for those things.
Laur Hesse Fisher: [00:09:49] So there are a lot of changes in store for our grid: It’s going to accept an increasing amount of variable wind and solar energy; and it’s going to get an even bigger draw as more electric cars come online and buildings start using more electricity for heat.
There is so much to dig into here, which is this entire season is dedicated to the future of low-carbon energy, which we’re doing in collaboration with the MIT Energy Initiative.
In the coming episodes, we’ll help you understand where our energy comes from now, the different options we have for reducing CO2 emissions, and the opportunities and challenges of these options. We hope that, when you vote or talk about these issues with your representatives, colleagues or friends, these episodes can help give you a foundation to make strong, informed decisions about our energy future.
If you’re hungry for more right now, search for MIT Energy podcast for the MIT Energy Initiative’s companion episode.
I’m Laur Hesse Fisher from MIT Environmental Solutons Initiative. Thank you to Harvey Michaels for speaking with us and, as always, thank you for listening.