Montclair Climate Action

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How does energy aggregation work?

For the past few years, Montclair has been part of the Sustainable Essex Alliance, which uses energy aggregation to obtain cheaper, greener energy for the residents of Montclair and surrounding towns. But there is a lot of confusion about how energy aggregation actually works, and I want to use this and future posts to try to make things a little clearer.

To be honest, energy aggregation can be really confusing. We all know that electricity is just electrons coming through wires — but how can I buy “clean electrons”? If I order a book or a food processor or a shirt online, the item goes directly from the seller to the me. But electricity doesn’t work that way. There is one electrical wire going into my house, and it is always delivered through that wire by PSE&G. If I change electricity providers to another company — say, Clean Choice Energy — it’s not like that company can deliver the specific “renewable electrons” from their solar panels or windmills directly to my house. Those electrons from Clean Choice Energy’s windmills and solar panels go into the electrical grid just like electrons from gas plants or coal plants or nuclear plants. So how am I getting “renewable electricity” if those electrons don’t go directly to my house, and they are all mixed up with the “dirty” electrons from other sources?

It’s a good question. Here is an analogy that might help. Think of electricity as being like water. When I turn on my cold water faucet, water comes out. If I also then turn the hot water tap, it’s still water that comes out, but it’s now warmer water. It’s still just water, but it’s a different mix of water.

Now imagine that I could choose between two different water suppliers — let’s call them Clean Water and Dirty Water– and there is a tap for each. I can get more Clean Water and less Dirty Water just by closing one tap and opening the other. As I close one tap and open the other, it’s still water that comes out, but the mix of water is different.

Electricity works like that. By buying more renewable electricity, it’s like I’m opening the tap on the renewable electricity supply that feeds into the grid. It’s still just electricity that comes out of the wire into my house, but the mix that goes into the grid (and ultimately, through the wire into my home) is different — it becomes “more renewable.”

So I don’t buy specific “clean electrons,” and in a certain sense it’s not pure “green energy” that is coming into my house. But by buying renewable energy, I am affecting the overall mix of electricity in the grid. By increasing the renewable electricity fed into the grid and reducing other sources of electricity, like fossil fuels, I am pushing the overall electricity supply in the direction of green energy.

That’s what happens when I buy renewable energy on my own. It’s a good thing to do, but the effect is small — real, but small. However, when a bunch of people get together, the effects can be quite large. To take Montclair as an example, there are 40,000 people in Montclair, and together we can make a much bigger difference. If I alone choose 100% renewable electricity, I’ll reduce carbon dioxide emissions by a few hundred pounds a year. But if everyone in Montclair choose 100% renewable electricity, then together we could eliminate 2000 tons of carbon dioxide emissions every year.

That’s why energy aggregation is so important. Of course, it also helps us negotiate a lower price, but just as importantly, it magnifies our impact.

What Montclair is doing is basically the same thing, on a smaller scale, that New Jersey does with its renewable portfolio standard (sometimes called a clean energy standard). Under New Jersey law, PSE&G and other utilities in New Jersey have to provide a higher and higher percentage of electricity from renewable energy. Currently, it is 22.5%. By 2030, it is supposed to hit 35%, and then 50% by 2050–still too low, but better than now. And just like energy aggregation in Montclair helps drive the move towards renewable energy, the RPS does that at the state level.

Clean energy standards work, and they are a key part of what has driven the shift towards renewable energy over the past few years (not the only thing of course — changes in technology have played a role, too, but CES policies are part of the picture). In fact, 2020 was the first time that renewables were responsible for more electricity than any source except methane gas. It just goes to show: when we work together, we can accomplish a lot more than when we work separately.