torstai 28. heinäkuuta 2016

Green Energy: Somebody Else's Problem


Now, I know this is a pretty large wall of (possibly somewhat incoherent, due to few rounds of re-writing and editing) text, and you might - due to various reasons - find this difficult or off-putting to read. In that case, please skip to the very end and read just the last two chapters. I've tried to sum all this up there, hopefully in easier-to-read fastion.

Recently I saw an article about how environmental organizations declare that Sweden could fully be powered by renewable energy sources by 2020. Renewables in this context typically means pretty much solar and wind, with some hydroelectric and maybe some other other sources (biomass and whatnot) thrown in, but majority would be from those two mentioned first. And I consider this kind of thinking pretty damn dangerous, at best.

I'm certainly rooting for renewables but when something like this is said, I want to see a plan. A real plan, with details on how the required amount of energy is generated, day by day. But of course they can't provide such a plan - when ambitious claim like this is made, people behind it look at two numbers: kilowatt-hours used in a country over a year, and number of kilowatt-hours generated. And why not - by ignoring the fact that energy storage is at the moment unsolved problem these claims can be made without being completely dishonest.

See, the problem with wind and solar is that they do not provide constant about of energy. The consumption of energy, however, is relatively constant and predictable. I'm more familiar with Finland's numbers so I'll use those here instead, but Sweden's numbers should be fairly similar.

Take this figure below (I think I've used this same figure in previous post). This is from the first week of this year which was quite a cold one. And dark one, mind you - solar production is essentially zero during the winter months here, due to northern location.

The red graph is total electricity consumption. You can see that energy consumption spikes during the days and is at lowest during nights, difference here being almost 2000MW. This same day/night variance is there, every day of the year, only in summers the difference is smaller, about 1000MW.

The black graph is domestic energy production. You may notice how it is way below usage graph. This, too, is these days fairly constant (unfortunately, I might add), only the amount of deficit varies. At the moment there is not enough domestic production so we import a lot of energy from Norway (mostly hydro) and Russia (who knows how that is produced, nuclear and coal very likely).

So here we have clear pattern; energy usage is relatively constant, with some day/night variation. And we can see the consumption here rising because it was cold that week, getting colder by the day. Heating takes a lot of energy.


Here is then wind production graph from the same period. Can you spot the problem already?

Oh, by the way, this data is directly from FinGrid, who manages the Finland's energy grid and thus is very well aware of what is being used and produced - and where.


The problem is that it's highly variable. Ignore the fact that there's just 600MW produced at peak; if we scale the total wind power production up ten or twenty times, we get a graph with maximum number of 6000 or 12000MW, but the zero point doesn't move. Graph will still have roughly the same shape (remember, this is entire country's wind generation, not just some small area; although not all windmills are included so there is some extrapolating included by data provider)

During that time period the wind power consumption was below 200MW until 11th day (with minimum hovering at about 100MW for about two days and in the middle of that period, on single day - 8th - it reached about 300MW in between), rising to about 600MW after that (for few days at least). So during the coldest, most power-hungry period of the year we have five days with less than third of maximum generation from wind and practically nothing from solar.

I don't know about you but in my book this is a major problem here. Do think about this:
Finland's maximum power usage there was (and is) about that 15000MW. About 2100MW of that is from hydro right now, and there really isn't any practical way to build more of that. Industry (paper mills for example) produces about 1100MW, let's assume that remains about constant. How much solar and wind you would need to realisticly cover that difference?

Now, this peak is always during the darkest, coldest time of the year, so unless there is ridiculous amount of solar the winter production is approximately nothing

And you do have to expect long dry spells with wind, like you see above; only about one sixth of peak power. Yeah, the figures will not be pretty. Either we'll be overproducing at crazy amounts at
times with no way to actually use it all (short of some methods of producing, say, hydrogen for fuel - again something that isn't realistic in near term), or we'd be badly short. Not good either way.

Energy storage? Okay, show me the storage system that can handle, let's day, full three days of shortage of "just" constant 3000MW. If you can point me to that kind of system, please show me, I'll really want to be proven wrong here! Electric cars are out immediately - people won't be happy if their cars will drain their batteries to the grid on the first day, never being able to recharge before full supply returns three days later, so it needs to be something else.
But let's look at larger scale yet. After all, we're next to Sweden (which was originally mentioned here), with their own presumably fully renewable grid. And their power situation is about as sorry as ours - no solar, almost no wind (due to geographical location right next to us, weather locally is fairly similar), just the hydro. So they need to import energy too! (or you know, they, too, would have had massively overbuilt wind, with same issues with variance mentioned above)

Norway (next to Sweden) has vast amounts of hydro, but even that has limits - they only can export that much before they, too, would be short. Certainly not enough for both Sweden and Finland. And there is also limit on how much international grid connections can transfer energy.

Russia then? Both Finland and Sweden would be importing energy from there (Sweden doesn't have land border so they would be connected through Finland's grid), and some from south, Estonia or Denmark and their grid with continental Europe connections. And when you go past national boundaries you really don't know how the energy is produced - in this case it very well could be mostly coal, imported from a country that doesn't care. Nasty, dirty, CO2-spewing coal. There goes any claims anyone could have about "green" energy. But apparently that CO2 doesn't count as it isn't produced here - despite the reason of those emissions very clearly is here.

Funnily enough, I've been told that this is the exact situation in Germany now: By shutting down their nuclear plants they can claim to be green, but in reality, just over the border in Poland there's lots of coal plants that feed the Germany's need for electricity when green sources happen to have shortages. I haven't verified if this is true, but at this point, considering above points about problems with wind and solar, it is way too plausible to ignore. I don't know about you, but I'll take nuclear power any day over horribly dirty coal.

Now, I deliberately have kept this speculation in very near future because that can be predicted somewhat easily, being just few years away. If we go past that, there might be actually viable energy storage methods used which can help out a bit. But I have some serious trouble imagining energy storages capable of even mentioned 3000MW output over even two days, which is something that would be needed when relying on wind and solar as much as green energy enthusiasts' want us to. And in countries with larger population this figure would need to be massively higher.

In the end, by externalizing the power production you only make it somebody else's problem. And how clean or dirty that production is, is pretty much out of your control. So much for the (near-term) green dependency. Short of some major - no, huge - energy density breakthroughs, it ain't happening.

So now the TL;DR:

Now, make no mistake, I am absolutely positive that we have to make serious and even drastic reductions to the CO2 output in global level. The problem here is that current actions that are being taken are proverbially making us jump out of the frying pan and into the fire. By making the easy choices - that is, building solar and wind - we must satisfy the highly varying production levels somehow as the electricity usage is fairly constant. "Smart grid" can only do so much before reduction options there run out. Add the fact that people want to shut down nuclear power - which is currently our best way to reduce dependency on coal and other fossil fuels - and end result is that we collectively end up producing more CO2, despite all the gloating articles how some country went on a full day using renewables. Just single day you say? Well, let me see the figures for the remaining of the year then.

Really, the path we have currently taken is not a dependable way forward. 



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