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Comment Re:Night? (Score 1) 252

What you propose is about 5TWh of total storage. Currently there are 40GWh. Increasing the current capacity 125-fold is just as unrealistic as increasing it 2000-fold, seeing how a company who now tries to push plans for the 13GWh pumped storage Atdorf (http://de.wikipedia.org/wiki/Pumpspeicherkraftwerk_Atdorf#Pumpspeicherkraftwerk_Atdorf , sorry, no English version) has been struggled for years with their plans, primarily against the opposition of the Green party.

So your plans is to build a ~30-by-30 kilometers sea that is elevated by 100 meters. Do you even realize how giant this thing is? It's the size of Berlin! Do you realize that you also need to multiple it by 2, since you also need a sea at the low level to store the water?

80TWh will never happen, and 5TWh won't happen either, and 1TWh is maybe realistic within 200 years or so. The renewable revolution will not happen, all we're doing now is going back to burning lignite and gas.

Comment Re:Night? (Score 1) 252

1) This storage capacity was calculated by simulating wind, solar etc. output based on real weather data. It already assumed a realistic mix of renewables including ones with adjustable output such as biogas and a realistic possibilities of export/import.

And about "firing up fossil plants for a few days in a year". Just imagine what would any electricity company do if they had a power plant that they would be able to use only a few days a year? They would immediately close and dismantle it and fire the staff, because the maintenance and standby costs would dwarf any profit from it.

Actually, this effect can already be seen here in Germany. We're far away from 100% renewables, yet in the wake of closure of several NPPs, and the ever increasing demand for backup power because of growing renewable supply, there is a huge debate about building additional coal and gas power plants. One would guess there's a gold rush building these? Nope. The major electricity producers already said that unless they can fire them close to 24/365, there's simply no profit in building them. The government would have to do the despicable and actually start subsidizing coal and gas power plants if they want a stable supply.

2. Solar might have a generation curve that matches the daily consumption. But seasonally, it doesn't match the consumption at all. The season of the peak consumption in Germany is WINTER, because of less natural light and warmth. At the same time, the solar production is very low in winter, it falls way below 5% of what it does in the summer. It's the saisonal fluictuations that need the storage, not daily.

3. This list is obviously bullshit. It lists Germany with THE AVERAGE PRICE of 27 $ct/kWh. it's like 21.5 euroct/kWh. I'd like that price! Where can I get it?

If you look at verivox.de, there's a price calculator at the top. You can enter the postal code (try 10000-13000 for Berlin) and your expected consumption to get the cheapest tariffs. The cheapest one I get is 411 euros for 1700 kWh a year. That's ~30 US-cents/kWh in the current conversion ratio. However it's a prepaid package which everyone would recommend to stay the hell away from. Last year a major "cheap" supplier suddenly went bankrupt and many people lost their prepaid electricity packages. The average prices are much higher, typically around 26-27 euroct/kWh.

About the taxes: the major factor is in the recent price increase in Germany was indeed a tax - a sort of a tax that is levied on the electricity consumers and used to pay the renewable electricity producers.

4. Well, guess what? Germany is a couple of hundreds kilometers long. Yet the wind power manages to fluctuate between near zero and the maximum all the time!

Comment Re:Night? (Score 1) 252

Oh, and about pumped storage: yes, it's the most cost-efficient storage method, but for the dimensions we are talking about, it requires too much space. For comparison: currently available pumped storage in Germany is 40GWh. In a regenerative 100% scenario, 80TWh would be required, the 2000-fold increase. Currently, there is a plan to build another storage sea with 14GWh, it's been in planning for the last 15 years and is currently confronted with massive lawsuits from the public who want to stop the project at any cost (nobody wants to have a huge concrete sea in their backyard), so it's anything but certain if it ever is going to be built.

Comment Re:Night? (Score 1) 252

You're forgetting some important things:

1. the household electricity consumption is only a minor part, the most is consumed by the industry, and you need to provide storage capacity for them as well.

2. The regenerative power like wind and solar is subject for a major saisonal fluctuations. Which means, the storage needs to be able to load all the energy during one season with high production and keep it for months so you can use it in a season with low production.

3. Currently, Germany is in a "20% scenario". We already have the highest electricity prices in the world (for a major country) ~26 âct/kWh and the import/export saldo in the area of 15% of total production. The electricity prices will likely increase by another 3-4 cents next year and so far there's no end to the price hike in sight.

In Germany, the electricity production/use is ~7500kWh per capita, so 1MWh storage is sufficient for just about 50 days. Considering that the assured production of wind power is below 1% (that is, 200MW in the entire country with over 25GW wind turbines) of installed capacity at 99% of assured supply (that would mean 3.5 days of blackout per year on average, in reality we have only ~15min, or 99.997% assured supply here), it's not that astonishing at all.

Comment Re:I wonder (Score 1) 248

Normally, CAESes, such as the on operating in Huntorf in Germany, IS burning natural gas. When storing energy, the air is pumped into the caverns. When extracting it back, the air may just turn the turbine directly, but this way, a lot of energy will be lost - the pumped air storage is tightly sealed, but the compression heat is inevitably leaking from the cavern.

What they normally do instead - they use compressed air as the input for a turbine burning natural gas - this way it does not need it's own compressor, making it more efficient than a conventional turbine. From 0.8kWh of stored electricity and 1.6kWh (thermal) of natural gas, they produce 1kWh of output electricity. Burning 1.6kWh gas in a normal turbine with 50% efficiency would produce 0.8kWh electricity, so the overall efficiency of this storage is just about 50% - or even less if you consider more efficient gas-and-steam power plants. Maybe this new CAES will utilize some more efficient technology, but don't expect wonders from it - this type of storage has quite high losses.

The CAES were never about storing power efficiently, their main advantage is the ability to power up really quickly. The Huntorf CAES for example is able to reach 50% output in just 3 minutes, and full output in under 10 minutes.

Comment Re:"Dumped on the grid" (Score 1) 160

All these "net zero" concepts are non functional without a grid, because they need it as a storage and they don't implement their own storage. And they assume this service is for free.

While such installations are rare, the service is indeed free, but the question is whether this concept will survive on a large scale - no it will not. If the amount of renewable energy increases and everyone just keeps using the grid as a free storage facility, the grid operator will have to invest more and more to extend this storage capacity. This includes maintaining of the true storage like the pumped water but also maintaining backup generation plants and transport capability. Other negative effects include lesser profitability of the conventional plants.

Sooner or later, this will require offloading of the additional costs to the consumers. Sooner or later the "net zero" facilities will have to pay additional fees for using the storage capacity of the grid provider.

Currently, this is what we see looming here in Germany - increasing amount of renewable energy while at the same time attempting nuclear phaseout leads to funny effects - the transport capacity of the one of the best maintained grids in the world are at limit and need massive investments. On the other hand, more gas power plants are needed to be built to be able to compensate random production - but they are getting less profitable. The effect is - the grid providers are currently pushing proposals for additional assessments on electricity - the consumers will soon have to pay additional fees for supporting extension of the grid infrastructure and for subsidizing of new coal and gas power plants. Either this be passed as law, or the providers simply increase their prices - either way the costs of the renewables have to be compensated and our already highest electricity prices in Europe and likely worldwide (currently ~27 eurocents/kWh on average) will skyrocket even further.
Science

Submission + - Jars of irradiated Russian animals find a new purpose (nature.com)

scibri writes: From the early 1950s to the end of the cold war, nearly 250,000 animals were systematically irradiated in the Russian town of Ozersk. Fearful of a nuclear attack by the United States, the Soviet Union wanted to understand how radiation damages tissues and causes diseases such as cancer. Now, these archives have become important to a new generation of radiobiologists, who want to explore the effects of the extremely low doses of radiation — below 100 millisieverts — that people receive during medical procedures such as computed-tomography diagnostic scans, and by living close to the damaged Fukushima nuclear reactors in Japan.

Submission + - Pacific 'garbage patch' changing insect mating habits (guardian.co.uk) 1

nachiketas writes: Marine insects in the Pacific Ocean are changing their reproduction habitats in response to environmental changes from the accumulating amount of rubbish in the north Pacific subtropical gyre, also known as the great Pacific garbage patch, according to a study by the Scripps Institution of Oceanography at University of California San Diego, published on Wednesday in the Royal Society journal Biology Letters. "This paper shows a dramatic increase in plastic over a relatively short time period and the effect it's having on a common North Pacific Gyre invertebrate," said graduate student and lead author Miriam Goldstein, in a statement released by Scripps. "We're seeing changes in this marine insect that can be directly attributed to the plastic."

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