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Comment by sandworm101 | Hacker News Reader

But remember that a square kilometer of solar panels needs maybe ten square kilometers of actual land. Anywhere other than at the equator, the panels need to be spaced far enough apart not to shadow each other. On a north-facing slop they would be even more spaced out. Do that in two dimensions, so they can track the sun, and keeping one square meter of panels perpendicular to the sun requires a suprisingly large footprint.

And trees. Clearcutting forests to make room for a solar panels just seems wrong, a Captain Planet style of evil. There are all sorts of places where the terrain just isnt suited.

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It's not 10x. The optimal ground coverage ratio in the South even for tracking panels is like 30%: https://www.sciencedirect.com/science/article/pii/S0038092X2...

Most of the US isn't wooded. I don't think a significant number of projects propose clear-cutting to build solar farms. I don't know where that came from.

Try where i am, the pacific northwest. Its all mountains and trees. Large solar farms are always tricky, even residential rooftop solar often runs into issues with trees.

If only it were possible to transmit electricity from one place to another...

Seriously, while a lot has been written about the need to update the grid and install more long distance transmission lines to support renewables, even with the current grid it makes much more sense to install wind and solar in locations where it is more efficient and then transmit the electricity elsewhere. In Texas, most of the wind farms are in West Texas hundreds of miles away from Houston, for example.

This might be a controversial opinion: In many cases, it might be reasonable to clear cut 10 sq km for solar power. Pacific Northwest is enormous. There is plenty of undeveloped land that can be used for solar power. To be clear: I am not suggesting "cut down all of the tree for solar". I am saying: Choose 1/5/10 sq km plots, clear cut them, and install solar power. Ten to one hundred of these in the region would have minimal environmental impact, but very large impact to reduce use of hydrocarbons for electricity production.

Then you probably shouldn't build large solar farms. Leaves still a huge amount of area open on top of roofs, parking lots, streets which could be used for solar without cutting down a single tree. Though it somehow didn't prevent those roads and houses to be build :p And while I don't like cutting down trees, just fire protection - and that gets an even larger topic in the future - should tell you to cut down trees directly around houses, so rooftop solar should be possible in most places.

But the thing is: the pacific northwest should be ideal for wind power. So that would be the main emphasis. And then build a high power line to Nevada. Which delivers solar to the northwest and in the nights wind power to Nevada.

Germany already has a 1.4GW powerline to Norway operational, where we network the grid to optimize renewable utilization.

Nobody builds solar farms on "north-facing slopes". Nobody is making solar panels "track the sun". Nobody even proposes "clearcutting forests" for solar farms. Trolling is in strict violation of site guidelines.

Well, actually Florida (FPL) along I-10 is right now constructing new solar farms where there used to be forests. I'm not sure if what they did with the trees constitutes "clear cutting" but the solar panels are there now, and the trees are not. I've driven the route for many years. It was all forested.

Do you know if those forests were professionally managed for paper production? It might be private land, and it very likely legal.

True. There isn't any actual untouched forest land in north Florida. It's all been harvested and replanted many times. Almost certainly it was private sale or leased land. But those farm trees still produced more oxygen and stored more carbon than the solar panels will.

> But those farm trees still produced more oxygen and stored more carbon than the solar panels will.

If those solar panels replace a coal fired power plant, is that still true? I am unsure.

> Nobody is making solar panels "track the sun".

It's very common for utility-scale solar to use single-axis trackers (the panels move from pointing east to pointing west through the day), unlike small-scale solar which usually has fixed panels (normally pointing south or north depending on which hemisphere you're on). The gain from single-axis trackers is high enough and their cost is low enough (a single geared motor can move a whole row of panels) to make it cost-effective.

(I haven't, so far, seen any large photovoltaic solar power plant which uses two-axis trackers to really track the sun; but thermal solar power plants with a central tower need these two-axis trackers to aim each mirror at the correct angle.)

I think trackers are a thing of the past. The cost of solar panels has sunken so low, they come essentially for free in installations. A tracker would be way to expensive. Here in Germany, people even start covering north-facing roofs with solar, and of course even walls and fences, if they are roughly in the right direction.

I'm not sure about the other things but sun tracking tech for solar panels has been around for a long time and it's trivially easy to find through a search, such as [1].

"But there are also other ways to boost the energy production of solar panels – such as by tilting them to follow the Sun's path in the sky, similar to the way young sunflowers follow the sun from east to west during the day. Tracking technology, which is already in use on some land based solar arrays, helps increase the overall electricity production, as the panels constantly adjust to face the Sun."

1) www.bbc.com/future/article/20221116-the-floating-solar-panels-that-track-the-sun

Trackers are necessary if someone is doing math based on panels perpendicular to the sun. Of course they are rare, but are needed when doing the conversion. Whether the tracked pannel cast shadow, or more panels recieve less-than-direct sunlight, the math is the same.

And it is all irrelevant. There is an absolute overabundance of pasture land, so spacing panels out so the grass can grow between and under causes no difficulty.

Good thing that cube of uranium doesn’t need any extra space around it! We can just line them all up next to each other. Criticality accident? What’s that?

Clear cutting forest to put in solar isn’t likely to be cost-efficient. There’s plenty of shitty desert and mountainside land available.

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