We're going to need a lot of solar panels • Hacker News Board

Re: We're going to need a lot of solar panels

#411

Post by walrus01 » Sat, Jul 23, 2022, 7:52 AM UTC

zaptrem wrote: post #391

Syonyk wrote: post #311

Earlier quoted context omitted.

It should run you about $0.75/W to install them and hook them in for a grid tie system, maybe a hair more. Interestingly, that's the same for roof mount (with rapid shutdown) or ground mount (without rapid shutdown). Costs vary slightly depending on what you're doing in terms of panel orientation and inverter DC:AC ratio (if it's not 1.2 or greater, add more panels). This project (CO2 to CH4) would benefit from maxim…

Why can't you put the panels on an electric swivel? I assume it's significantly more expensive? Why?

A sun tracking ground mount that goes on a steel pole and can take the wind loading of just six 1.65 x 1.0 meter size 60 cell panels costs considerably more to buy, ship and install than the panels themselves. These days if you need more kWh per month your money is much better spent buying more fixed mount panels.

Re: We're going to need a lot of solar panels

#412

Post by yayachiken » Sat, Jul 23, 2022, 7:53 AM UTC

illiac786 wrote: post #376

KingOfCoders wrote: post #356

Earlier quoted context omitted.

Not sure how "better insulation" is something "renewable enthusiasts conveniently forget". We need better insulation either way.

I think what this person meant is the renewable enthusiasts treat insulation as something easily done whereas it will take 100 years to insulate the majority of houses in Europe in my view…

I know you are just illustrating an opinion and not meaning it literally, but I want to stress how ridiculous your number of 100 years is in reality.

The expected economic lifetime of a building in Germany is approximately 100 years. Which means that on average, the house will be torn down and rebuilt after at most 100 years, because additional upkeep would not make economic sense.

This means that if you do not change policy except mandating modern standards for new buildings (which is already done) and do literally jack-shit, the normal economic activity will have the problem sorted out in that timespan.

For reference: Of 22 million buildings in Germany, "only" 12.5 million are built before 1977.

The German government aims at having pretty much all buildings energetically renovated in 2050.

The biggest problem is that 1. there are many house-owners who literally do not give a shit even if they can save lots of money by an investment. Not everyone is economically minded and there is no political will (or legal basis) to force these people for their own good. And 2. for bigger apartment buildings etc. it is hard to do an invasive renovation while the units are occupied, limiting the scope of renovations to something that can be done in-place or one unit at a time or without affecting tenants.

Re: We're going to need a lot of solar panels

#413

Post by taneq » Sat, Jul 23, 2022, 7:53 AM UTC

ekianjo wrote: post #399

jnsaff2 wrote: post #334

Earlier quoted context omitted.

With all due respect, looking at your numbers my hunch is that you need better insulation. I know a person who has about 10kWp installed on a passivhaus here in latitude 59N and says that having a heat pump is overkill for them.

> better insulation better insulation is not cheap and therefore not everyone can afford to do it. Also the same people who want renewables are usually opposed to building new housing so there's that.

It's not super expensive, really. And this is something that building codes can address - either via the gentle option of requiring all newly built dwellings to be thermally efficient, or the somewhat more assertive route of requiring any home sold to have adequate insulation.

Re: We're going to need a lot of solar panels

#414

Post by ncmncm » Sat, Jul 23, 2022, 7:54 AM UTC

goethes_kind wrote: post #19

oceanplexian wrote: post #13

Earlier quoted context omitted.

On one hand it’s an interesting engineering challenge, but I am always perplexed how covering hundreds of square km of an ecosystem with glass is “good for the environment”. It sounds like something future generations will shake their heads at while trying to dispose of all the toxic waste.

Matter of interpretation. Is humanity at all good for the environment? Some would say no. Solar is clean and deserts are mostly, well, deserts. And climate change seems much worse than having a tiny bit of our deserts being used for PV farms.

Pointless to discuss. Deserts are a really dumb place for solar farms.

Solar will coexist with agricultural land and existing reservoirs, and benefit both.

Re: We're going to need a lot of solar panels

#415

Post by brazzy » Sat, Jul 23, 2022, 7:54 AM UTC

betwixthewires wrote: post #392

tppiotrowski wrote: post #363

Earlier quoted context omitted.

I think solar panels are a bit more efficient at converting sunlight > electricity than the chemical process of sunlight > photosynthesis > decomposition > burning fossil fuel. Take the ICE that only coverts something like 20% of fuel into motion, the rest is lost to heat. The electric motor is far more efficient. You'd need to update your reasoning to take into account all the efficiencies lost in the fossil fuel cr…

No I don't, and I'll tell you why. The amount of energy hitting the surface of the earth is constant, assuming that the luminosity of the sun is constant. Photosynthesis as cyanobacteria/chloroplasts/chlorella perform it might be less efficient than a modern solar panel at converting the entirety of the spectrum to energy, but they did it and produced this fuel for hundreds of millions of years. Even if you get 10 ti…

>Let's say I'm off (in your favor) by a whopping order of magnitude.

No, let's say that you are off by three or four orders of magnitude. Because your first estimate really is that bad, and without it, your entire "argument" falls apart.

Re: We're going to need a lot of solar panels

#416

Post by jiggywiggy » Sat, Jul 23, 2022, 7:56 AM UTC

m12k wrote: post #409

isoprophlex wrote: post #349

Earlier quoted context omitted.

The catch is that power-to-gas tech described in the article will allow you to store the power produced in summer. Produce excess methane gas in summer, store with existing infrastructure, burn it for baseload/winter.

From the article: "Just as converting chemical energy in the form of fuel into electricity endures 45-75% thermodynamic losses, converting electricity back into chemical fuels loses 60-70% of the energy in the process. Converting solar power into natural gas only to burn it in a gas turbine power plant could help with long term seasonal energy storage but is so much less cost competitive than other ways to stabilize…

It might be less cost effecient at the moment. But I kinda like the decentralized nature of it.

Re: We're going to need a lot of solar panels

#417

Post by ncmncm » Sat, Jul 23, 2022, 7:56 AM UTC

ghostpepper wrote: post #114

rektide wrote: post #75

Earlier quoted context omitted.

It'a really weird but there's a surprisingly growing base of farming amid a solar farm, where apparently many plants just cant stand the pure sun & benefit from some periodic shade during the day. I dont know how much I believe it but combined agriculture/solar use seems perhaps legit to be a thing. Also, solar panels dont seem that difficult to recycle. There's already a decent & growing reclaimation market. Giant s…

> Also, solar panels dont seem that difficult to recycle. There's already a decent & growing reclaimation market. Curious if you're basing this on firsthand knowledge? I know nothing about solar panels but I've read some stories[0][1] lately about difficulties recycling them, particularly older ones that were deployed 10-20 years ago and are now reaching EOL. [0] https://www.discovermagazine.com/environment/solar-pan…

Ultra-pure silicon is intrinsically valuable. Anyone dumping used-up panels is an idiot.

Re: We're going to need a lot of solar panels

#418

Post by walrus01 » Sat, Jul 23, 2022, 7:58 AM UTC

tuatoru wrote: post #394

walrus01 wrote: post #53

Earlier quoted context omitted.

> parking lots This is how much of downtown Tulsa, OK is covered in parking lots: https://i.redd.it/ukzcn1xx6cc91.jpg There is no technological problem to covering a parking lot in PV, it's a question of the political will and money to do it.

There's no scale shown on that photo. What is the total area?

I've never actually been to that city but that's a mid sized sports stadium you see to the left side. Tulsa I think is an extreme example, if you look at an aerial photo of Seattle from the 1970s there were a ton of "downtown" surface lots too, but now the land is way too valuable to use for that.

You can also see what looks like a regulation size baseball diamond to the top right side.

Re: We're going to need a lot of solar panels

#419

Post by JohnHaugeland » Sat, Jul 23, 2022, 8:00 AM UTC

isoprophlex wrote: post #349

Helmut10001 wrote: post #320

People both underestimate and overestimate what PV can do. In summer and around noon, here in western Europe, there is so much PV-electricity produced that it is _almost_ enough to fulfill all demands. In winter, the amount is like a drop in the desert. I have built a 30 kWp PV at home 2 years ago - you would think this is quite big, for a private plant. It is not enough. If I want to power a heat pump (with drilled…

The catch is that power-to-gas tech described in the article will allow you to store the power produced in summer. Produce excess methane gas in summer, store with existing infrastructure, burn it for baseload/winter.

> The catch is that power-to-gas tech described in the article

isn't real

Re: We're going to need a lot of solar panels

#420

Post by ncmncm » Sat, Jul 23, 2022, 8:01 AM UTC

Dma54rhs wrote: post #94

Gwypaas wrote: post #85

Earlier quoted context omitted.

When talking about pumped hydro the roundtrip efficiency usually is around 70-80%. Not even close to batteries but way more scalable. Chemical storage is horrific. Creating diesel and burning it in a turbine or similar you start at 40-50% for the burning phase, without even converting anything in the first place. If you go the fuel cell route you tend to end up somewhere at 40-60% efficiency. So no, the only use case…

How is it as scalable when you're at the mercy of the local geology? There are not that many places where pumped storage is viable, its not just pumping water up to some random hill.

Except, it really is just pumping water up a hill. Siting for pumped storage is overwhelmingly easier than for hydro generation. The latter needs a watershed. A dike around a hilltop does not.