Why should I care about the electricity grid
I just want low carbon electricity, I am happy to let the politicians sort this out.
If you care about building more wind and solar, then you also need to care about the electricity grid.
The biggest barrier to more renewables is not money, they now already make financial sense, it's the ability of the electricity grid to cope with them. If we cannot find a way of managing the grid for the future, we can kiss goodbye to ever being able to build all of the renewable (low carbon) electricity generation that we need.
This is a discussion we cannot just leave to the electricity industry and the politicians. If we want progress we all need to get involved. Which means we need to understand the problem - and the solutions. This is potentially as big as fossil fuels, but it gets a lot less attention. As we always say, there is no pain free solution, but there is a way that gets us to where we want to be at a reasonable cost.
I want us to add a whole lot of new renewables into our electricity grid, but I also want the decision makers (investors, regulators and governments) to be realistic about what we need to do to allow this to happen, and it's not just building new wind farms or adding more solar panels.
Yes, its complicated - but at its core its simple
On Friday we published a long blog (on our ghost site) on how to keep the electricity grid stable, and on Monday we published a second piece on the same theme.
On Sunday, I wrote a summary for our substack followers, and normally that would have been it. But on Sunday evening I got a message from a good friend I went to university in New Zealand with. Andrew also did engineering, but after graduation we went different ways. I ended up in finance and he became a farmer and an environmentalist. Andrew went all in, and over the decades he has turned the family farm into a sustainable business.
So, the message from Andrew was simple “I am sorry mate, but I have no idea what you are talking about”. So after about 20 messages back and forward I found a way of explaining it that made sense. Which to be fair, I should have done right from the start.
The electricity grid - for non engineers
Before you start reading this - none of what we write about here is a reason not to add a whole lot more wind and solar electricity generation to our system. The problems we describe are fixable, but we need to have an honest discussion about this, especially as regards the cost. And, you do not need to know anything about how our electricity system works - or be an engineer, to understand what we need to do.
So here goes. First point, our electricity grid is all of the power lines/cables you can see (unless they are buried, plus a whole lot of equipment (substations etc) that controls everything.
Pretty much everyone I know, including Andrew, thinks the electricity grid is like a pipe. It takes the electricity from the power station (or these days the wind or solar farm) to our homes, offices and factories. Sometimes storms etc take the power lines down, but most of the time the pipe just works.
The problem with that image is that while it's right in some ways, it's wrong in some really important ones. And while the wrongness didn’t really matter when we used fossil fuels (mostly gas and coal) to fuel our power stations, it does matter now.
Its like driving a car - but not being able to speed up or slow down
So, why is the pipe image wrong? Some really basic physics. The amount of electricity that goes into the grid, must always equal the amount that goes out. If it doesn’t then all of that complex and sensitive equipment that controls the grid disconnects, it shuts down. It is all designed to do a very specific job, within very tight constraints.
It's a bit like driving a car that you have to keep at exactly 50mph. Regardless of the road conditions. If you slow down or speed up by just 1%, so 49.5mph or 50.5mph, the car will stop. And yes, those numbers are correct, it really is that hard.
So, sticking with the car analogy, what causes the grid to speed up or slow down?
The historic reasons were a surge in demand (what used to be known as the “kettles on in the advert break” phenomenon) and a power station going down unexpectedly.
The good news was that the fossil fuel power stations had a lot of what is called inertia. It’s the same thing that allows your car to keep freewheeling long after you have finished coming down the hill. In their case it's due to the massive weight (called mass) of the turbines - hydro power stations have this as well.
But, wind and solar don’t have this mass. They connect to the grid via electronics, which are another example of things that shut down when the grid gets to 49.5mph or 50.5mph.
And it gets worse. Wind and solar are variable - which means that on a regular basis they don’t generate electricity. So on a regular basis they stop. A bit like before when a fossil power station went offline, but more frequently.
So, we have an electricity grid system that has to work within very tight tolerances, but we now have more events that throw it out of balance. And when they do, it can just stop - basically we get blackouts.
And this problem gets bigger and bigger as we add more renewables and shut down the old fossil fuel power stations. We end up with more unbalancing events and less protective mass/inertia.
The good news is that we have lots of solutions.
That's the bad news. The good news is that we have lots of solutions. We can bring in electricity from wind and solar that is generated a long distance away, where the sun is still shining or the wind is still blowing. And we can use batteries to store electricity when we have a surplus, to release it when we have a shortage. That is what we wrote about in last Fridays’ long blog.
And there is a lot of smart software that manages demand and better uses the grid infrastructure. Which is what we wrote about on Monday.
All of these things can keep the grid in balance even in the absence of fossil fuel power stations. And then we can keep adding more and more renewables without causing more blackouts. But, as we said at the beginning, these solutions cost money, we need to invest starting now.
So hopefully by now you get why having a stable electricity grid is really important if we want to add a whole lot of new renewables - lots of wind and solar. The next blog on this topic will start describing what we need to invest in to deliver this, but that's a topic for another day.
If we want the future to be different, we need to make it happen. We cannot expect someone else to fix this for us.