Readers reply: Why put solar panels on green space when we could put them over car parks?

The long-running series in which readers answer other readers’ questions on subjects ranging from trivial flights of fancy to profound scientific and philosophical concepts

I would like to know why we build solar farms over green space, when we could just put them over massive car parks as a popular current internet meme suggests. Chris, Middlesbrough

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Readers reply

Sure … and how about mandating that data centres put them on their roofs? Come to think of it, perhaps solar panels should be added to all new structures. DrBlamm0

For the same reason that we insist on storing water in lakes even though millions of people have sinks. That might be a bit flippant, but bear with me. The real answer is that we can do both and we don’t have to choose. Solar panels on car parks would be good for local generation to take strain off the grid and I encourage people to make it happen – the more local electricity generation, the better.

But for national-level generation, you need much bigger installations. NESO, the National Energy System Operator for Great Britain, has to balance the generation sources across the country and fine-tune the frequency being delivered to homes. To do this, they ask generators to switch on and off throughout the day. It is much easier to do this with one very large installation than 100 smaller ones on top of car parks. Person123456789

Good analogy. Extending it slightly, millions of people have water tanks in the loft. It helps smooth out peak demand and reduces required capacity in the distribution network. There’s been a transformation change in the price of battery storage over the last five years. Distributed generation has become a much more useful part of the strategy for electrification of energy supply and a good match for solar panels on car parks and the top of every structure we build. It also might be worth mentioning that solar panels are now cheaper per square metre than roof tiles, so there’s no excuse not to deploy them everywhere. imperialforce

The amount of farmland used by solar panels is negligible. Sure, put them on car parks, but they cost a lot more that way – every metre off the ground is more steel and more resistance to wind load needed. It’s not a reason to stop building ground-mount solar, the cheapest source of new electricity available. Most of the time, “we could put that somewhere else” is just an excuse to not build anything at all. pavanne

Start with putting them over golf courses. How come the people outraged about farmland never get enraged about how much good land is used for golf? Five to six times that used for solar farms. Secret_squirrel29

It’s more expensive, yes, and very few companies are going to do it voluntarily. Just give them no choice. Car parks, warehouses, leisure centres – everywhere. While we’re on the subject, line motorways with wind turbines. The scenery has already been “scarred” by the road, and all motorways link towns and cities, so the power should be easy to distribute. Now, stop talking about it and do it! LeroyB

Of course, this is a false dichotomy – car park and greenfield are not mutually exclusive. We should do both. MaynardSmithFan

In France, they had to make it a planning requirement for car parks to include them – that way, it’s not just a question of money. Once they’re up, you see it makes a lot of sense – shade for the cars while also generating useful amounts of electricity to recharge them. wyldfam

It has just been legislated this year – 40% of the roof [40% of the ground-floor area of the building in homes built in England from 2028] should be solar panels. Randomusername222

I would support renewables being installed by default over car parks. I’d also want to see it become commonplace for members of the royal family to be buried beneath car parks, like they did with Richard III. Undoubtedly, these are the major planning reforms that successive governments have failed to deliver. Dorkalicious

Put them on pontoons and float them on reservoirs – it would help reduce evaporation as well as providing green electricity – or next to train tracks, where presumably you don’t have to worry about grid connections. Stoichenens

There are solar panels above rivers and open water in China; it is often called “floatovoltaics”. China is the global leader in this, as well as many other things, good and bad. Lovecars

We conveniently forget that car parks, warehouses, shopping centres, football pitches, golf courses and vineyards have been built on what were fields for food production. GardnerJoe

Giant warehouses and now vast datacentres, power distribution networks, solar farms … are we so mad we can’t coordinate the requirements of communities and industry? Why must we always be at loggerheads? Communities invest in green spaces only to find them being reoccupied by whatever the next growth spurt demands. Would it not benefit everyone if we simply required datacentres to include closed cooling and power systems with a view to generating thier own power and reusing water in a closed loop? We should work toward locating these objects where they don’t encroach on people – who got there first, but have no say in government-endorsed industrial change happening all over their investment. You only get one go at finding a happy place. Stuart_Dixon