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http://www.dry-it-out.com/cool...

A 10m x 10m room x 2m ceiling requires 12KW to cool it. I made the numbers easy to simulate an entire house and give 100sq meters of panel.

https://dothemath.ucsd.edu/201...

A standard solar panel produces about 250-300W per square meter in such regions. Therefore you'd need about half your roof space to cool just one room, and nothing else. Call it a two-storey house (upstairs and downstairs) and you can *just* about cool the house if you do nothing else with it.

https://news.energysage.com/12...

"As of January 2018, the average cost of solar in the U.S. is $3.14 per watt ($37,680 for a 12 kilowatt system). That means that the total cost for a 12kW solar system would be $26,376 after the 30% Federal ITC discount"

You would literally be spending something on the order of $35k just to cool your house. That's an annual wage. If you can't afford the air-con (notice that the article is just as much about "poorer countries can't afford air con, hotter countries cost even more to air con), $35k on top of the investment to power it is a huge amount.

https://www.ovoenergy.com/guid...

That would buy 437,500 KWh of electricity in India, for example, which would keep that same 12KW powered for.... 99 years.

What you're asking is "Why can't people just spend 100 years of their cooling electricity usage in one hit so that they don't have to pay for any more cooling? On top of the price of the cooling system, and not including maintenance, replacement, fitting, etc. of either."

Germany's economy is larger than CA but using renewables they have more energy than they can use.

Nope.

During brief times of year, that MAY be true, as with the headline you are thinking of where German power pricing was negative on Christmas day in December.

However most of the time Germans are importing power because they shut down all nuclear plants - they are currently producing about 35% of their power from renewables

But all that importing and expensive renewable power facilities means that Germans pay some of the highest power rates in the world. Even if on Christmas you do get a break because the office buildings are shut down...
 

How did you arrive at "10^9 hashes per joule?" Your link states: "Power Efficiency 0.098 J/GH +10% at the wall." And that is approximately 0.1078J (adding 10%) for 10^9 hashes. So 1 Joule gives 92.78e9 hashes.

So the energy for 1.2e19 hashes is:
1.2e19 / 92.78e9 = 0.129e9 joules

0.129e9 joules = 33.333 kWh
https://www.rapidtables.com/co...

1 kWh price = 8 cents in China and 12 cents in the US
https://www.ovoenergy.com/guid...

So the energy cost per second using the currently most efficient hardware = 33.333 * 0.08 = $2.66 in China, or $4 in the US. That seems pretty cheap.

Well, it does not really make sense to use the peak output of a power plant and the 'assumed households number' it can supply to calculate the average power consumption of those households.

Your mind gymnastics was for nothing. Of hou had tried to take a capacity factor into account it would have been more fruitful, but still not leading to the goal :)

See here: https://www.ovoenergy.com/guid...

https://www.ovoenergy.com/guid...
Let's go with U.S.A. electricity prices since they're more or less in the middle.
Let's also say you have a higher-than-average computer, with an Intel Core i7 3970X Extreme Edition at 150W.

12 cents for one kilowatt for one hour. 150W means 0.018 cents per hour. 3600 seconds per hour, so USD$0.018 / 3600 = 0.000005 cent per second.

Let's say you're generous and let them mine on your computer for ten minutes. That's USD$0.003, less than half a cent.

Yes, damn those damn crypto-mining scripts! I let my guard down for a whole 10 minutes and they cost me less than one-third of a cent! And that's if crypto-mining actually was able to draw 150W from your CPU, using all cores at 100%.

So in the grand scheme of things, what would you prefer:

1. Ads that requires multiple address lookups, slow down your connection, add more delays for viewing the actual content you're trying to read and just be totally annoying to look at, distracting you and preventing you from reading?

2. Crypto-mining in the background, a single thread of our multi-core processors, at maybe 20~50% capacity of that one core out of two/four/eight+ cores?

Usually these renewable reports are grossly exaggerated to make it seem like renewable is more capable than it really is. But this one is actually fairly accurate. 10 MW * 0.097 capacity factor = 970 kW 970 kW / 2500 homes = 388 Watts per home Average UK home annual consumption is 3940 kWh 3940 kWh / 1 year = 450 Watts average consumption.

A 6 MW facility, when operating at 100%, will feed the 4 KW average demand of about 2500 homes. With a .097 CF, this demand will be met an average of 10% of the time, but since output is actually variable, the equivalent of 10% of the time. So the remaining 90% of demand from those homes must be provided by another source.

Usually these renewable reports are grossly exaggerated to make it seem like renewable is more capable than it really is. But this one is actually fairly accurate.

10 MW * 0.097 capacity factor = 970 kW
970 kW / 2500 homes = 388 Watts per home
Average UK home annual consumption is 3940 kWh
3940 kWh / 1 year = 450 Watts average consumption.

So their "homes powered" metric is fairly close to accurate (2150 homes would be exact). We'll go with the exact 450 Watts per home figure.

To put this in perspective, the proposed Hinkley C nuclear plant would have a 3.2 GW capacity. Using the 90% capacity factor for newer nuclear reactors, this would give an actual generation of 2.88 GW, or enough to power 6.4 million homes.

At a construction cost of 24.5 billion GBP (the UK has some of the most expensive nuclear in the world), this works out to 3828 GBP per home powered.

If you run the same calculation using the 70% capacity factor for the UK's older nuclear plants over the last 5 years, it works out to 2.24 GW. Enough to power 5 million homes at 4900 GBP per home powered.

Unfortunately none of the news reports on this new solar farm that I was able to find mention its cost. This site estimates a utility-scale solar installation in the UK costs about 1.1 GBP per Watt. That works out to 11 million GBP / 2150 homes = 5116 GBP per home powered. But it doesn't include the cost of the 6 MW battery.

At an optimistic 100W, that's 87600 kWh/year (24 * 365 * 100 / 1000). At 12 cent/kWh (source, the exact number doesn't matter, I just want a rough estimate), that's over one thousand dollars per year.

Congrats: even if you get the PC for free, a Turris Omnia will pay for itself in less than a year in the US (I live in Germany, which according to the above source is 35 cent/kWh, so even in less than half a year, probably a quarter or so. I own a Turris :-).

And yeah, the Turris is on the expensive end of the scale.

They need to do a better job, then? Because once you adjust for purchasing power of different currencies, Germany has about the most expensive electricity in the world (save for a few small island nations). Yes, it's renewable - it also is twice that of their nuclear powered neighbor, France. So kudos, Germany - you've proved that you can occasionally spike high in "renewables" generation for only twice the price of a sane, nuclear power approach!

I don't want to belittle this because India is one of the places where solar actually makes sense. But even there its capacity factor is only about 20%. Compared to 14.5% for the continental U.S. and about 10% in Germany. Capacity factor is the ratio of actual electricity produced (after taking into account night, weather, angle of the sun, downtime due to maintenance, etc) to nameplate (maximum) capacity.

So while it's capacity is 648 MW, its average electrical generation over a year will only be about 20% that, or a more modest 130 MW. Electricity costs about 8 cents/kWh in India. So payback time (excluding operational expenses and interest on loans) will be

($679 million) / (0.2 * 648 MW * 3600 sec/hour * 8766 hours/year * $0.08/kWh) = 7.47 years

India is one of the better places for solar. (The 150,000 home figure seems a little screwy, since 648 MW / 150,000 homes = 4320 Watts, which is about 3.5x the electricity consumption of the average U.S. home. I suspect the 150,000 homes figure already took into account capacity factor, and is not "at full capacity" as TFA claims.)

Yes the cost is big. But everything about nuclear is big, including the amount of power generated. Fukushima Daiichi consisted of 6 reactors:

#1 generated 460 MWe from March 1971 to April 2012, or 41.1 years
#2 generated 784 MWe from July 1974 to April 2012, or 37.7 years
#3 generated 784 MWe from March 1976 to April 2012, or 36.1 years
#4 generated 784 MWe from October 1978 to April 2012, or 33.6 years
#5 generated 784 MWe from April 1978 to Jan 2014, or 35.7 years
#6 generated 1100 MWe from October 1979 to Jan 2014, or 34.2 years

Multiply the generating capacity by the time in service and you get 165.7 TWh for reactor #1, 259.1 TWh for #2, 248.1 TWh for #3, 230.9 TWh for #4, 245.3 TWh for #5, and 329.8 TWh for #6. For a total of 1478.9 TWh.

Nuclear's capacity factor in Japan (ratio of actual electricity generated vs peak capacity) started around 46% in the mid-1970s, and had reached 79% by 2001. Assume a linear increase followed by it remaining stable from 2001-2014, and overall capacity factor over this timeframe (which conveniently breaks down into 26 and 13 years) is (26*(.46+.79)/2 + 13*.79) / 39 = 0.68.

So actual electricity generated by the plant would be about 1478.9 TWh * 0.68 = 1005.7 TWh. Round it down and call it an even 1000 TWh.

The average price of electricity in Japan is 26 cents/kWh. Yes the price was lower in the past, but we want the inflation-adjusted total value of electricity generated, so using today's price is valid.

1000 TWh * $0.26/kWh = $260 billion worth of electricity produced over the lifetime of the plant. Even with the second-worst and most expensive nuclear accident in history, the Fukushima Daiichi plant still produced more value in electricity than the cleanup cost.

Now consider that the world generated 2731 TWh with nuclear in 2008. If you go with 20 cents/kWh as a global average electricity price, that's $546 billion worth of electricity generated by nuclear power each year. Add up the cost to clean up Fukushima ($200 billion), Chernobyl ($200 billion), and Three Mile Island ($1 billion). Amortized over the 37 years since the first of those accidents, the cost of cleaning up these nuclear accidents only works out to ($401 billion / 37 years) / (546 billion / 1 year) = 1.98% of the cost of electricity produced.

Basically, the cost of cleaning up nuclear accidents is just 0.4 cents/kWh.

and many others, even if maybe they miss out what seems to be this scheme's USP, adding solar power to it.

It's not hard to find such comparisons. From the link, France has a cost of $0.19 per kWh, Germany has $0.35 per kWh. The US has $0.12 per kWh.

What are the costs for that offshore wind electricity? Germany is about 3X that of the US and Denmark, the leader in offshore wind generation, pays even more. So yeah - they can do it, but it's quite expensive. Perhaps there are more cost effective means of generating power?

Your own link contradicts what you're claiming. Germany and Denmark have the highest prices (unless you know how to avoid paying VAT and the other taxes) in part because they subsidize their green energy production which drives the overall price up significantly. Plenty of other sources show this as well.

I don't know the specifics of the Australian market, but I would imagine some kind of fuckery is going on, possibly similar to what happened in California where someone in the private sector stumbled on some highly exploitable government policy. If a government tries to regulate a market in a way that makes it possible or easy to exploit, someone's going to do it, especially when the payout looks good. Same holds if the government starts granting private companies monopolies similar to the U.S. cable industry. Of course you're going to get stuck with a single provider, shit service, and a shit price when it's illegal for anyone else to compete.

Also, Australia has loads of the Thorium. Nuclear would be a a great investment for their future. You suggest that the government needs to "fix the market" as if that wouldn't create an equal amount of bureaucracy and regulatory bodies. No matter how much green power you invest in, unless you massively overbuild, you need something to serve as a solid base, unless you want to invest the tends of billions of dollars in a storage solution that'll be just as obsolete in a few decades.

Dumbshit, German users don't pay three times the price of energy.

Wanna bet?

https://www.ovoenergy.com/guid...

Germany - 35 cents per KWh
US - 12 cents per KWh

Where do you live?

Texas

I pay 7 cents per kWh for my office power and 10 cents per kWh for my house power, both coal.

It would cost me 10 cents per kWh for my office to be powered by 100% wind and 13 cents per kWh for my house to be powered by 100% wind. Solar isn't even an option here (at least from the power companies).

In most parts of the world you can't lose with solar now.

Generally in the 1st world, only those nations that have stepped in and either subsidized solar or taxed the crap out of everything else. Sure, in Germany where you pay 35 cents per kWh, yea I'm sure solar makes sense. But so what, they are paying up to 5 times my power rates.

https://www.ovoenergy.com/guid...

https://www.eia.gov/todayinene...

https://www.ovoenergy.com/guid...

Both have base rates in the high teens, plus taxes, to net at 35-40 cents per kWh retail. The US levelized costs also include these costs (about a third of Denmark or Germany retail costs).

https://www.ovoenergy.com/guid...

That says German average price is 35 cents per kWh.

Do you dispute that number being the average across Germany?

The US number given is 12 cents, and that is accurate for the average, but I pay much less, just over 7 cents in Texas. That doesn't make the 12 cent number wrong, just that it isn't MY number.

Maybe your number is lower, but I suspect that 35 cents is correct as a national average in Germany.