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Comment by piyushpr134 | Hacker News Reader

The current largest solar park in India and possibly the world, on google maps here https://www.google.com/maps/place/Thirumani,+Karnataka+57213...

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Wow. I kept zooming out and there was more and more. That is incredible.

Do you know how much power it produces?

Just eyeballing it there seems to be 1 square kilometer of panels total. At regular solar panel efficiency, output would be 1000-2000MW total. So the same order of magnitude as one nuclear reactor.

I think you’re off by a factor of ten. Sunlight is about 1 kW/m^2, so 1 km^2 (=1e6 m^2) would only be 1000 MW at 100% efficiency, 100-200 MW at 10-20%. That said, the plant looks bigger than 1 km^2 to me.

The wikipedia link shared above by aunty_helen ( https://en.wikipedia.org/wiki/Pavagada_Solar_Park ), which matches the name in the google maps link, says 53 km^2.

It also says that it could produce 600MW by the end of January 2018, can produce 1400MW now, with 650MW more under construction. It also says 2000MW capacity being planned for by the end of 2019.

I'm not sure how much of the 53 km has active solar panels, but they'd only need 3.8% efficiency to hit 2000MW with that much area.

Thanks, I didn’t see the link earlier. I’m glad to see it’s the array which is bigger than estimated. :)

More like 10 sq km so far. You'll see it if you zoom out more. There are plenty of panel "farms" in other parts of the town. More details here: https://en.wikipedia.org/wiki/Pavagada_Solar_Park

Google map has a area measuring tool enclosed if you right click.

Closing a region gives you approximate area.

edit: There seems to be at least 35 sqkm.

Looks to be this one: https://en.wikipedia.org/wiki/Pavagada_Solar_Park

So 600MW scaling to 2000MW

almost 2000mw now (2GW)

Well that's the coolest thing I've seen all day, then

Is it normal for the panels to tilt north-south? Wouldn't it be better if they tilted east-west?

I assume they are at a fixed angle and don't change tilt throughout the day. Usually in the northern hemisphere south-facing is the best (the sun spends most of the day in the southern part of the sky but equal parts in east and west). Similarly you think of a south-facing side of the building as getting "the most sun" and design accordingly.

Wow, they don't track the sun? It seems a single motor can tilt the whole row of the panels with some relatively simple tilting mechanism. Heck, with gears a single motor can probably tilt multiple rows, since they need to move so slowly.

Because a solar panel's efficiency is proportional to the cosine of the angle to the sun, you actually don't gain that much performance from east-west tracking -- it's maybe 20-30% better.

These days, the panels themselves are cheap enough that it makes sense to just buy more of them, instead of adding enough motors and mechanical components to move panels that weigh millions of pounds in aggregate.

Yeah, the industry has been back and forth on this one - having a mechanical system incurs extra cost and maintenance for surprisingly marginal gains. Now that panels are cheap it's easier to just have more of them.

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