Most of the world will eventually be able to run entirely on renewable energy, primarily using solar power and storage. There’s a long transition towards it and it may prove politically difficult, but technically it is fairly straightforward. The parts of the world that are trickier are those that get less sunlight during the winter, right at the point when overall energy needs are at their highest.
In the global north, we need energy for heating, and renewable heat is a massive technical challenge. Efficiency and good design can reduce our needs for heating, and we’ll be able to electrify some of it. Another obvious place to start is with the existing infrastructure of the gas network. We can add biogas and gas from waste, and with some tweaks to the grid, we can also use hydrogen.
There are experiments in various places around Europe and beyond, testing ways of using more hydrogen in heating. I reported on one at Keele University recently. It can be used in transport and industry as well, and we’ll be hearing a lot more about hydrogen in future, either as gas or as fuel cells. Using renewable energy to generate that hydrogen is, hopefully, going to be one of the big stories of the 2020s.
Hydrogen is created in an electrolyser, which uses energy to split water into oxygen and hydrogen. This can be done at small scale, and in Japan some home-owners have domestic electrolyers called Ene-farms which create hydrogen for electricity. (A company in Germany has just begun marketing a domestic electrolyser as part of a whole-home energy system, and I’ll come back to them another time.)
Ideally though, we’d be adding hydrogen to the grid, rather than relying on individuals to buy and fit their own decarbonisation technologies. We’ll never get to net zero without mass technologies that reach people whether they are interested or not, whether they live in houses or apartments, and whether they rent or own.
This week I read about an idea for making that as direct as possible. Danish wind power company Orsted and hydrogen company ITM Power have jointly proposed fitting an electrolyser into an offshore wind turbine, potentially in the tower itself. It would be a wind turbine that produces gas rather than electricity.
The clean power generated by the wind turbine would be put to work immediately, with no grid losses from dispatching electricity to a hydrogen plant. Rather than connect the turbine to the power grid, you would connect it to the gas grid instead. As well as being more efficient, this could potentially be cheaper. Everything happens on the offshore platform, so there’s just the one site and that makes it easier to get permits. And hydrogen gas pipes are cheaper than high capacity power lines, so there would be a saving in the connections.
This is just a proposal at this stage. It might not come to anything. But it will be ideas like this, measures that can deliver larger scale quantities of affordable hydrogen, that will determine whether hydrogen becomes a mainstream part of the solution. Ideas like this increase the possibilities for decarbonising the gas grid. I’ll be interested to see if it happens.
The Earthbound Report 
“Most of the world will eventually be able to run entirely on renewable energy, primarily using solar power and storage.” What makes you think there are enough raw materials lying around to power the world on disposable solar panels and store energy (presuming primarily in again, disposable batteries)?
What’s a disposable solar panel?
They have a ~25 year life span until the power output starts decreasing, don’t they? Very little out of a used solar panel can be recycled back into anything useful. I’m off grid with 1kW solar panels and lead acid batteries… not looking forward to the day I need to replace them.
alek, they’re typically warranted for 25 years, but usually the warranty says they will produce ~80 to 90% of their rated power after 25 years. In other words, if they haven’t failed (and the failure rate is pretty low) then they are almost as good as new
That’s all correct, but am I the only one seeing the elephant in the room?
We didn’t pick these solar panels off the solarpanel tree. They were created using industrial processes with fossil fuels and made with raw materials at the cost of ecosystem destruction. And that’s just the panels, how about energy storage when the sun doesn’t shine? Sure there are some great ideas in compressed air and water at a height, but that won’t do for cars and most residencies. What is the life span of a lead acid or lithium ion battery and what is it’s production and disposal ecological footprint? 95% of my home energy comes from solar, before anyone labels me a fossil fuel shill.
There’s nothing renewable about the way renewable energy is implemented in today’s homes and cars since the raw materials used to make the tech are non-renewable. Why is that so hard to accept?
Hydrogen has tiny molecules so escapes very very easily. It is also extremely explosive when mixed with air. I fear that the existing gas pipe network might not be able to contain and transport it safely…but surely people are looking into this?
Yes, lots of research going into this. Part of it is to do with the pipework – plastic being better than metal.
Those are all fair questions Alek, though something having a lifespan isn’t the same as it being disposable. Everything has a lifespan, and an environmental footprint from creating it. Solar panels pay back their embedded emissions within two years.
It’s important to note that the energy used is renewable – ie sunlight. As you say, the technology itself may not be renewable, but that is changing. It is now possible to recycle batteries, and as there are more and more out there, there’s a huge business opportunity in making that easy and cheap. It is also technically possible to recycle solar panels, though whether this happens in practice or not depends on local regulations. In the EU, manufacturers are responsible for the end of life of any electrical products they create, so the EU will likely be the leader on PV recycling. I’ll have to write about this at some point.
Seems to me part of the problem here is to imagine moving from a consumer culture where everything is made to be eventually thrown away and recycling assuages our guilt; to a maintenance and repair culture where everything is made to last forever by being maintainable, repairable and being able to be reused or re-purposed, and recycling is seen as a sign of failure.
Where I see a ‘life expectancy’ of 25 or 30 years, I expect, through maintenance and repair, for the item to last indefinitely. Solar panels typically have aluminium frames, glass covers and silicon PV cells. Quite apart from the fact that silicon and aluminium are the second and third most abundant elements in the earth’s crust, the panels should be made so that the cells can be replaced by re-crystallising the silicon, which is only around 5% of the total panel. See https://www.cedgreentech.com/article/can-solar-panels-be-recycled, but look at the maintenance of such a panel, not it’s total recyclablity, and you can see that only a tiny percentage – the silicon cells – needs to be replaceable.
Using wind power for gas is an interesting idea, but one of the big problems of solar energy is variability of supply. Even with careful demand management and storage capability, a significant over-capacity would, I believe, still be required, especially if we are not going to use highly dangerous nuclear energy. So I would suggest we need dual-purpose wind – electricity to meet peak demand and possibly gas at low demand, which is better than just switching the turbine off.
When trying to get people to image a solar economy, I ask: ‘What do you do with all that spare capacity when the sun is shining, the wind is blowing and the tides are flowing?’. I give two possible answers – make aviation fuel and fix nitrogen for fertilizer. Note that the very first commercially successful process to fix nitrogen used electricity from a hydroelectric project in Norway, but the availability of cheap oil and gas and the discovery of the efficient Haber process meant that it was never developed.
Since aviation fuel would be in high demand in a solar economy, I suggest that using spare solar electricity capacity to make hydrogen is probably not the best way to go – better to develop a process to make methane which can then be used to make aviation fuel as well as being fed into the gas grid.
I imagine wind turbines in the North Sea surrounding a re-purposed natural gas production platform. I also imagine people saving money by insulating their homes, and using that saved money to at least occasionally fly to a holiday destination, with cheaper aviation fuel because of the saved energy demand for heating.