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No, renewable are incredibly expensive, on the contrary. Why is that? Because renewable produce when wind blows or sun shines, and not when we need power. That'
by wazoox 7y ago
No, renewable are incredibly expensive, on the contrary. Why is that? Because renewable produce when wind blows or sun shines, and not when we need power. That's the first point, we need to produce exactly as much energy as we consume, at any time. Renewables fail utterly at that, and that's why renewable energy appears so cheap when you simply consider the price at which it's sold on the markets: production occurs at random times when it isn't needed, pushing market prices down in the toilet. But that's an undesirable side-effect, and not a good thing.
Renewable produces only a fraction of their nominal output (typically 15-20%), and at random times. So typically a huge, sprawling 12km2 900MW solar plant produces a small amount of power during the year, in the best case (in the desert) 1.4TWh, while a 900MW nuclear reactor produces typically (actual numbers) 6.5TWh every year.
You also need to complement renewable production with an equivalent amount of steerable power (usually natural gas), or a large amount of batteries which multiplies the price by 5, 10 or more. So you can't consider the renewable price alone; you must take into account the price of the substitute power source, too... And its environmental price!
So renewable energy is cheap because it isn't worth much. It puts extra pressure on the grid, it forces nuclear plant to run at reduced capacity, which reduces the yield, and artificially lowers their profitability for no good reason at all.
In fact, renewables, by reducing profitability of nuclear power, has another very undesirable side-effect: making nuclear power companies cut corners on safety to save money.
Renewable power is better than coal; but it isn't, by large, as good as nuclear.
- fsh 7y agoDo you have any sources for your claim of batteries multiplying the cost for renewables by "5, 10 or more" in a realistic grid scenario? Did you take into account that most energy storage is done with hydro, not batteries? I haven't had time to carefully review the literature, but there seem to be quite a few papers that claim that storage for a 100% renewable grid would not be such a big issue.
- wazoox 7y agoBasically renewables produce 15-20% of the time (30 to 40% for offshore wind). Let's be generous and start with 30% of the time. You need storage to provide 70% of the demand. So for every GWh or required power, you need 700MWh of storage. The famed Tesla Mega battery is a puny 129MWh... You must account for the fact that there could be no sun or no wind for several days, therefore be able to store incredible amounts of power, far beyond the scale we know of.Then the sheer space required for renewable power is staggering. As I said, the biggest solar plants are 600MW to 1GW and occupy tens of square km. Now imagine supplying 10s of GW this way. As someone joked on twitter, if you covered the whole Fukushima exclusion zone (250 km2 or so)with solar panels, it wouldn't come close to the Daishi nuclear plant annual power output. For a detailed discussion on these matters, see https://jancovici.com/en/energy-transition/renewables/100-renewable-electricity-at-no-extra-cost-a-piece-of-cake/ https://jancovici.com/en/energy-transition/renewables/100-re...
- deleted 7y ago[deleted]
- fsh 7y agoYour calculation does not make much sense (GWh isn't even a unit of power). One would have to look at actual power production and consumption curves in order to estimate the required storage capacity. Battery storage is still very exotic, pretty much the entire capacity is provided by hydro nowadays. Current-gen solar panels average about 30 W/m² over the year in Japan's latitude and climate. So a solar park the size of the Fukushima exclusion zone would produce around 7 GW on average which is more than the combined nameplate capacity of the six reactors (5.3 GW). Supplying the entire country with electricity (~114 GW) would require about 3800 km² of solar panels, or about 1% of Japan's area.
- wazoox 7y agoGWh is the most relevant unit: the quantity of energy we need around the year. GW of nominal output is relevant for nuclear or fire-based power that can produce 24h/24 365d/year, but completely irrelevant for wind and solar that provide power only part time. A 1GW solar plant outs 1GW once every sunny day, at noon. The rest of the day, it produces less, and nothing at all 12 hours a day. A 1GW solar plant roughly produces 3GWh a day. OTOH, a 1GW nuclear plant produces on a yearly average 800MWh every hour, every day and night. So at the end of the year your 1GW solar plant produced a grand total of 1100GWh, while your 1GW nuclear (or coal-fired, or gas-fired) power plant produced 7000GWh. Plus your solar panel will provide energy mostly around noon, need it or not. While the nuclear (or gas, or coal) plant will provide power exactly when you need it. Wind is even worse than solar, because production yield isn't even particularly predictable. So when wind blows, electricity goes into the grid without any consideration for the need for it. That's why its price drops to negative at times: because we don't need it. That's not because wind is wonderfully efficient or something. It's because building wind farms is a fantastic misallocation of resources. We're literally spending money for electricity worth almost nothing, and it won't ever recoup its costs. That's why Germany, after having dumped 300 billions euros on wind farms in 20 years, stop building them altogether in 2018. At some point some accountant did the math.
- wazoox 7y agoI like that people downvote without providing any argument, any numbers or any source. Slow clap. Enjoy your blackouts.
- dang 7y agoCan you please read https://news.ycombinator.com/newsguidelines.html https://news.ycombinator.com/newsguidelines.html and stick to the rules when posting here? They explicitly ask you not to go on about downvoting like this. In addition to being tedious and doing no good, such comments often end up being false, once users come along and (as they typically do) give corrective upvotes to the unfairly-downvoted comment. Unfortunately, posts like yours here don't then garbage-collect themselves—they stick around, adding noise to the thread. That's one reason we ask people not to post them.
- stjohnswarts 7y agoI agree, unless there is a huge increase (2 orders of magnitude) in the ability to store energy per cubic meter per dollar then nuclear is the only path forward for bulk energy increases.