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How Windmills as Wide as Jumbo Jets Are Making Clean Energy Mainstream

nytimes.com

161–170 of 285 posts

Re: How Windmills as Wide as Jumbo Jets Are Making Clean Energy Mainstream

#161
post #2

As the production costs with windpower decrease due to the technological progress, the question of grid storage and grid interconnection becomes more pressing. E.g. in Germany, they frequently have days of negative energy prices, where producers need to pay to feed energy into the greed because of overproduction of energy on windy/sunny days [0](in German). Without storage and grid interconnection, there is only so m…

Can you explain why you think these negative prices are a bad thing? I think they're an efficient use of market based tools to ensure that the group who can reduce the input to the grid does so, and to incentivize electricity production that can meet the flexible demands of the grid (e.g. slow ramping coal would be penalised over fast ramping gas without any regulation needing to specifically target the coal and the…

Negative price signals that cause solar or wind production curtailment is essentially throwing clean energy away.

Negative prices are a helpful market signal, but must be combined with battery storage requirements.

Re: How Windmills as Wide as Jumbo Jets Are Making Clean Energy Mainstream

#162

I'm sorry, stupid question, but exacly how much power do those big ones generate? 20 times more than what? This actually most crucial tidbit isn't even covered in that article, or am I blind?

The biggest ones produce over 5 megawatts at peak capacity, I think someone has built over 10 megawatts but I'm not sure. 5 megawatts is a pretty useless figure for most people to imagine, and I think imagining it in units of homes-powered isn't great either because we don't have a sense of the heat or kinetic energy equivalent because our homes are quiet machines. A 260 horsepower car (think new minivan) at full thr…

> I think someone has built over 10 megawatts but I'm not sure.

GE just announced a 12MW turbine, which will start appearing in real world projects in 2020.

Re: How Windmills as Wide as Jumbo Jets Are Making Clean Energy Mainstream

#163
post #110

I like this article. I like that is has nice big pictures and videos, but they dont do that stupid big 'screenspace' image thing that seems to be popular in these sorts of articles now. Also their control centre looks horrible. Wheres all the crap on their desks? I hope they only just had to tidy it away for the sake of a press photo.

The guy on the left appears hard at work looking at an empty Windows desktop.

Well... at least on one of his 3 screens.

Re: How Windmills as Wide as Jumbo Jets Are Making Clean Energy Mainstream

#164

Selling solar back to the grid has one major problem that, fortunately, doesn't plague windmill installations: The Duck Curve [1]. The problem is that peak energy usage now occurs after sunset . So no matter how many solar panels you stack on your home, around 6-7 PM the coal, oil, and gas power plants all have to spin up to their max capacity. Your solar panels are new less likely to _replace_ a coal power plant, al…

* This leads to the power companies naturally feeling rather sour about being forced to credit residents for the power they supply to the grid during low-demand hours. Their costs are staying about the same, but now their revenue stream goes down.*

Time to get rid of coal? What the Duck Curve indicates to me, is that California's grad-scale solar really should be located about 6 hours time difference to the west. How about ocean solar farms located in the plastic laden mid-Pacific gyre? They could be equipped with plastic harvesting equipment.

Re: How Windmills as Wide as Jumbo Jets Are Making Clean Energy Mainstream

#165

Earlier quoted context omitted.

When power gets more expensive in the evenings, a lot of heating/cooling/charging loads may shift in time. Also, hvdc grids let you transmit over a couple of timezones. (And wind does not have the problem the first place, obviously)

If possible, but it may only get worse. If EVs become more prevalent, it will only increase the evening demand as most people will charge when they get home from work. Sure, maybe with timers you can shift that to midnight or something, but it's still happening at a time when Solar adds nothing. You can't just toss out something like HVDC grids as a quick solution. That kind of infrastructure takes decades to build o…

How long to EVs take to charge? Should be pretty simple to put a time delay into the charger to _begin_ charging around 2 AM when energy usage has gone back down again.

Re: How Windmills as Wide as Jumbo Jets Are Making Clean Energy Mainstream

#166

Selling solar back to the grid has one major problem that, fortunately, doesn't plague windmill installations: The Duck Curve [1]. The problem is that peak energy usage now occurs after sunset . So no matter how many solar panels you stack on your home, around 6-7 PM the coal, oil, and gas power plants all have to spin up to their max capacity. Your solar panels are new less likely to _replace_ a coal power plant, al…

You need a surprisingly small battery to shift use a mere 4 hours.

This is why we need market rates for power, for everyone. If I have a bunch of panels and my power is worthless at 2pm, that's fine. A small battery system will pay for itself quickly if that power is worth peak at 6pm. Or maybe I set my car to charge in the early afternoon? Maybe when I install my system, I put my panels facing West instead of south?

Re: How Windmills as Wide as Jumbo Jets Are Making Clean Energy Mainstream

#167
post #144

Earlier quoted context omitted.

Heating and cooling needs are fairly inelastic temporally. Your house is going to get cold in winter and hot in summer. You'll need to consume energy for this which is largely during the evening when everyone returns from work as you have fewer and fewer single income families. The refrigerator runs through the day. Sure you can set the dryer and dishwasher if you have one to run at a time when the power rates are lo…

You can add components with high, desirable thermal mass to your heating/cooling system to time-shift that as well. You heat and cool your thermal mass when energy is cheap and then use your thermal mass to heat and cool your house much more efficiently during expensive energy periods.

In most cases adding a swimming-pool sized tank of water to your house complete with a heat-exchange system to save $40 a month on your electric bill isn't going to be very economical, let alone practical.

Re: How Windmills as Wide as Jumbo Jets Are Making Clean Energy Mainstream

#168
post #135

Earlier quoted context omitted.

No, you need to consume what other methods, e.g. wind, are producing when there isn't the demand to use it.

There is always demand. The issue is that sometimes demand exceeds supply. Taking away supply has the same net effect as increasing demand. EDIT: with the one caveat of transmission capacity, which certainly can be an issue.

I don't think you're quite getting this. There are times where there is excess demand, even when removing these stores. What's so hard to understand?

Prices go negative in the US at times and in Germany more often. That is exactly when something like this would be used: to store that capacity.

Re: How Windmills as Wide as Jumbo Jets Are Making Clean Energy Mainstream

#169

Earlier quoted context omitted.

You can add components with high, desirable thermal mass to your heating/cooling system to time-shift that as well. You heat and cool your thermal mass when energy is cheap and then use your thermal mass to heat and cool your house much more efficiently during expensive energy periods.

In most cases adding a swimming-pool sized tank of water to your house complete with a heat-exchange system to save $40 a month on your electric bill isn't going to be very economical, let alone practical.

While correct, if you already have a pool, the heat exchanger equipment to use the pool as a thermal sink is eligible for a 30% federal tax credit (as long as you’re installing to heat/cool your house with it, not heat/cool your pool).

Re: How Windmills as Wide as Jumbo Jets Are Making Clean Energy Mainstream

#170
post #140

Earlier quoted context omitted.

California and Hawaii have already implemented price curves that make purchasing solar + storage viable for homeowners. As more states adopt these policies and more homeowners adopt batteries the duck curve can be solved. Also battery storage gives the added benefit of not needing a gas generator when the grid goes down if you have an islanding system!

How does one implement a price curve? By supply & demand, it is just the result of energy production + energy usage. Are you saying that California has somehow made energy scarce during the day or are you talking about price manipulation?

The price of buying/selling to/from the grid is different at different times of the day. Artificially set by the utility. Different utilities have different rules. In some you can take advantage of the arbitrage if you have a battery; buying during the day and selling in the evenings.

Exe here is San Diego's pricing from the perspective of consumption only: https://www.sdge.com/residential/pricing-plans/about-our-pri...

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