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, although they do change how many hours a day it runs.
Unfortunately for the power companies, running a coal power plant for 3 hours a day costs just about as much as running it for 8 hours a day. 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.
In some regions (Utah/Idaho/Colorado is the one I'm aware of) these power companies are now negotiating with governments for lower and lower solar credits for these kinds of residents and they're winning because the abundance of solar power at mid-day is legitimately creating an oversupply, thus making that energy worth less and less.
I see this causing problems for many of my neighbors, who had solar sales reps factoring in energy buy-back rates from 2016 into 10-year loans models to pay for the solar panels. Soon the energy the power companies pay my neighbors is going to offset their panel loans less and less, which may result in a reversal of the economics that led to them buying the panels in the first place.
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?
>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.
Where are you getting this assumption from?
In hot climates like Arizona, peak energy usage during the summer months is in the afternoon, not the evening. When it's 115 degrees outside, that's when everyone's A/C is running at full capacity. It gets cooler in the evening and A/C usage goes down then.
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!
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)
It only takes a little bit of battery capacity to shift the duck curve, and is a nice lead into the market ramping up volume to cover more and more capacity and time. It's also an power time-cost arbitration model which is very comprehensible to financial backers.
There was a very interesting article about hydrogen fuel cell cars posted on HN the other day, one of the things they mention is that excess energy could readily be diverted to hydrogen manufacture.
* 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.
The solution is straightforward - lower consumer electricity rates when power is cheap, and raise them when it is expensive. Consumers will naturally shift the elastic part of their electric demand to when power is cheap.
For example, charging the car when power is cheap.
The market should be able to handle this. Thus, the government should create the curcumstances this can occur, which means in practice that timeslot-based tarifs should be enabled.
The interesting question is what effect clean energy has to the usage of hydrocarbons. Will it bring reduce global demand or just reduce the price of energy.
The good news is: CO2 emission intensity is going down globally and emissions per capita in US, China and EU28 are going down.
The bad news are: Emissions per capita are still going up globally, and hydrocarbon usage and CO2 emissions are breaking records year after year. http://folk.uio.no/roberan/img/GCP2017/PNG/s09_FossilFuel_an... Economic downturn was the only thing causing temporary decline.
It looks like clean energy reduces the demand in developed countries, thus reducing the prices of hydrocarbons. It will not reduce the CO2 emissions globally, it just moves them from the developed world to the developing world. Maybe it slows down CO2 emission growth rate?
EDIT: Just to point out how complex the dynamics between clean energy, hydrocarbons and policy are, here is nice recent research paper from Acemoglu and Rafey:
>Abstract: We show that, in a model without commitment to future policies, geoengineering breakthroughs can have adverse environmental and welfare effects because they change the (equilibrium) carbon taxes. In our model, energy producers emit carbon, which creates a negative environmental externality, and may decide to switch to cleaner technology. A benevolent social planner sets carbon
taxes without commitment. Higher future carbon taxes both reduce emissions given technology
and encourage energy producers to switch to cleaner technology. Geoengineering advances, which
reduce the negative environmental effects of the existing stock of carbon, decrease future carbon
taxes and thus discourage private investments in conventional clean technology. We characterize
the conditions under which these advances diminish—rather than improve—environmental quality
and welfare.
If clean energy manages to get cheap enough eventually it will be easier to synthesize simple hydrocarbons out of atmospheric and water than to drill them out of the group and we can end up carbon neutral as a whole. We'll see how cheap midday solar ends up when the price finishes dropping.
Avoid this phrase at all costs. It is a buzzword used by the likes of the clean coal lobby. Global warming isn't tied to emission intensity, but net emissions. The fact that CO2 emissions are down relative to economic growth, but are still climbing, is not useful. It is PR turd-shining.
> it just moves them from the developed world to the developing world
This is a really good point, clean energy seems to be a luxury at the moment.
No one can blame poorer countries, they aren't all in a position to invest in renewables, for many of them it would be crippling, the argument that renewables is sometimes cheaper only works long term, and long term takes significan't up front investment, burning coal etc takes significantly less.
Emissions continue to go up because relatively speaking renewables are still a small portion of the global energy use and the need for more energy is still rising fast (renewables or not).
I assume just the fact that companies (and consumers to a smaller degree) can install solar power and then generate "free" electricity plays a non-insignificant role in getting them to use even more electricity.
However, I don't think that's what causes most of the rise. It's all the planned obsolescence electronics we use and throw into the garbage every 2-3 years and other stuff like that. We simply need more energy to build more stuff. At least if we go 100% renewable power and electric vehicles, that will minimize the impact on the planet, even if we double our energy use over the next 50 years.
There will also be new energy efficiency technologies that will at least slow down our increase in energy use.
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 much renewable energy from intermittent sources like wind and solar you can handle.
Germany has at least one example of an aluminium producer testing dialing the power use of their melter up/down by 25% in response to input from the grid [1]:
> Trimet says that implementing its technology across Germany’s four aluminum smelters, three of which it owns, could provide a demand response capacity equal to a third of Germany’s 40 gigawatt-hours of pumped hydro storage.
There was a lot of confusion about this one when it was published, but as the article points out, they're not using their molten aluminium pools as a liquid battery - they're merely dynamically adjusting the electricity usage of their hydrolysis cells, which also requires some other adjustments to keep the process going, but it's still a lot of power and more responsive than what they do today (which involves taking the smelters entirely offline for short periods).
It helps that their test plant is near Hamburg in the North, "close" to most of Germany's wind turbine capacity which helps alleviate transmission/interconnection problems to the South.
As turbines get larger, not only do the costs go down, but the reliability of supply goes up. It becomes more economical to place them out at sea, where winds are more reliable, and the size allows them to run more effectively off low speed winds. These turbines are claiming 60%+ capacity factor, compared to 20-30% for smaller, onshore turbines.
The UK is already up to about 15% of its electricity from wind right now, these developments will open that up significantly more. Obviously at high levels of penetration there are going to be issues, we'll just have to see how far we can go, but even 25-40% of electricity would be a huge contribution.
Combine that with the new and existing nuclear, another 15%, some biomass and tidal lagoons, with the rest from gas (which produces half as much CO2 as coal) and it will go a long way towards meeting the UK's 80% CO2 reduction target from 1990 to 2050.
Isn't this where pumped storage and other forms of storage come into play? Here in Scotland we routinely pump water back up into our lochs in order to store it for future use.
There's also various news articles reporting on German mines beginning to be used as pumped storage sites, with a reservoir on the surface, and water dropping into the mines below when there's sudden demand.
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.
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 throttle is producing about .2 megawatts, so the worlds largest turbines are generating the same power as 10/.2=20 minivans at full power.
Another way to think of it is in terms of heat. A big stovetop burner will generate about 3000 watts of heat, so a minivan is like 65 burners at full blast, and a 10 megawatt turbine is like 3300 burners.
Based on their marketing (far quieter, 40% more energy) it seems like an interesting option. I know one of the biggest complaints that farmers have is the noise they cause, so they have to be placed far from houses.
I'm curious to see if it's mostly fluff or has any potential... but I'm not expert on the subject.
> Lower costs, though, have also made wind power more appealing elsewhere. Once mostly concentrated in northern Europe, Mr. Nauen is optimistic that new markets will emerge in Asia and the United States.
South America too. In just the last 12 months, installed capacity in Brazil went from 10.4 GW to 12.5 GW (source: Boletim Mensal de Geração Eólica - ONS).
The engaging cinematography on this article really drew me in. Somebody could write an article about brick laying and if it had the same Nutella-smooth video I would read the entire thing.
I happened to be driving through Indiana this week and saw the biggest wind farm I'd ever seen. It just went on for ages as we drove. I think it is this 600MW farm: http://meadowlakewindfarm.com/
I live here in Jutland, and it is indeed heartening to see those giant wind mills spread out across the fields. Surprisingly so many can be found inland.
I wish they focus as much on micro grids as much on energy generation.
Wow glad I have great internet the footage was great/visual is more direct.
Those turbines appeared to have an upward inclination, curious why that is. Also interesting that the trailing edge near the hub isn't as sharp as the tips probably due to slowest rotation.
Good stuff, those things are seriously massive.
I also like that giant wall monitor with all the 'stats'?
These little boats can continuously monitor the foundations of offshore wind turbines for scour, and their larger brethren can quickly deliver supplies in a wide range of weather conditions -- without putting human engineers at risk.
Money-shot on p66. About 8 months for EROEI (Energy returned on energy invested). I worked on some of these Life Cycle Analyses and can attest that they were quite rigorous.
[+] [-] coryfklein|8 years ago|reply
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, although they do change how many hours a day it runs.
Unfortunately for the power companies, running a coal power plant for 3 hours a day costs just about as much as running it for 8 hours a day. 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.
In some regions (Utah/Idaho/Colorado is the one I'm aware of) these power companies are now negotiating with governments for lower and lower solar credits for these kinds of residents and they're winning because the abundance of solar power at mid-day is legitimately creating an oversupply, thus making that energy worth less and less.
I see this causing problems for many of my neighbors, who had solar sales reps factoring in energy buy-back rates from 2016 into 10-year loans models to pay for the solar panels. Soon the energy the power companies pay my neighbors is going to offset their panel loans less and less, which may result in a reversal of the economics that led to them buying the panels in the first place.
[1] https://en.wikipedia.org/wiki/Duck_curve
[+] [-] pkulak|8 years ago|reply
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?
[+] [-] magduf|8 years ago|reply
Where are you getting this assumption from?
In hot climates like Arizona, peak energy usage during the summer months is in the afternoon, not the evening. When it's 115 degrees outside, that's when everyone's A/C is running at full capacity. It gets cooler in the evening and A/C usage goes down then.
[+] [-] IpV8|8 years ago|reply
[+] [-] fulafel|8 years ago|reply
(And wind does not have the problem the first place, obviously)
[+] [-] protonfish|8 years ago|reply
[+] [-] digikata|8 years ago|reply
[+] [-] vosper|8 years ago|reply
http://www.thedrive.com/tech/14431/are-hydrogen-cars-the-nex...
[+] [-] stcredzero|8 years ago|reply
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.
[+] [-] skookumchuck|8 years ago|reply
For example, charging the car when power is cheap.
[+] [-] sharpercoder|8 years ago|reply
[+] [-] nabla9|8 years ago|reply
The good news is: CO2 emission intensity is going down globally and emissions per capita in US, China and EU28 are going down.
The bad news are: Emissions per capita are still going up globally, and hydrocarbon usage and CO2 emissions are breaking records year after year. http://folk.uio.no/roberan/img/GCP2017/PNG/s09_FossilFuel_an... Economic downturn was the only thing causing temporary decline.
It looks like clean energy reduces the demand in developed countries, thus reducing the prices of hydrocarbons. It will not reduce the CO2 emissions globally, it just moves them from the developed world to the developing world. Maybe it slows down CO2 emission growth rate?
http://folk.uio.no/roberan/learnmore/more_warning_signs.shtm...
---
EDIT: Just to point out how complex the dynamics between clean energy, hydrocarbons and policy are, here is nice recent research paper from Acemoglu and Rafey:
Mirage on the Horizon: Geoengineering and Carbon Taxation Without Commitment https://economics.mit.edu/files/14855
>Abstract: We show that, in a model without commitment to future policies, geoengineering breakthroughs can have adverse environmental and welfare effects because they change the (equilibrium) carbon taxes. In our model, energy producers emit carbon, which creates a negative environmental externality, and may decide to switch to cleaner technology. A benevolent social planner sets carbon taxes without commitment. Higher future carbon taxes both reduce emissions given technology and encourage energy producers to switch to cleaner technology. Geoengineering advances, which reduce the negative environmental effects of the existing stock of carbon, decrease future carbon taxes and thus discourage private investments in conventional clean technology. We characterize the conditions under which these advances diminish—rather than improve—environmental quality and welfare.
[+] [-] Scarblac|8 years ago|reply
If they don't, there is so much demand for the stuff (burning it is so incredibly useful) that it'll all be burned.
[+] [-] Symmetry|8 years ago|reply
[+] [-] sandworm101|8 years ago|reply
Avoid this phrase at all costs. It is a buzzword used by the likes of the clean coal lobby. Global warming isn't tied to emission intensity, but net emissions. The fact that CO2 emissions are down relative to economic growth, but are still climbing, is not useful. It is PR turd-shining.
[+] [-] tomxor|8 years ago|reply
This is a really good point, clean energy seems to be a luxury at the moment.
No one can blame poorer countries, they aren't all in a position to invest in renewables, for many of them it would be crippling, the argument that renewables is sometimes cheaper only works long term, and long term takes significan't up front investment, burning coal etc takes significantly less.
[+] [-] mtgx|8 years ago|reply
I assume just the fact that companies (and consumers to a smaller degree) can install solar power and then generate "free" electricity plays a non-insignificant role in getting them to use even more electricity.
However, I don't think that's what causes most of the rise. It's all the planned obsolescence electronics we use and throw into the garbage every 2-3 years and other stuff like that. We simply need more energy to build more stuff. At least if we go 100% renewable power and electric vehicles, that will minimize the impact on the planet, even if we double our energy use over the next 50 years.
There will also be new energy efficiency technologies that will at least slow down our increase in energy use.
[+] [-] LMYahooTFY|8 years ago|reply
[+] [-] unknown|8 years ago|reply
[deleted]
[+] [-] delbel|8 years ago|reply
[+] [-] shaqbert|8 years ago|reply
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 much renewable energy from intermittent sources like wind and solar you can handle.
[0]: https://blog.energybrainpool.com/bereits-103-mal-in-2017-neg...
[+] [-] vidarh|8 years ago|reply
> Trimet says that implementing its technology across Germany’s four aluminum smelters, three of which it owns, could provide a demand response capacity equal to a third of Germany’s 40 gigawatt-hours of pumped hydro storage.
There was a lot of confusion about this one when it was published, but as the article points out, they're not using their molten aluminium pools as a liquid battery - they're merely dynamically adjusting the electricity usage of their hydrolysis cells, which also requires some other adjustments to keep the process going, but it's still a lot of power and more responsive than what they do today (which involves taking the smelters entirely offline for short periods).
It helps that their test plant is near Hamburg in the North, "close" to most of Germany's wind turbine capacity which helps alleviate transmission/interconnection problems to the South.
[1] https://www.greentechmedia.com/articles/read/german-firm-tur...
[+] [-] Brakenshire|8 years ago|reply
The UK is already up to about 15% of its electricity from wind right now, these developments will open that up significantly more. Obviously at high levels of penetration there are going to be issues, we'll just have to see how far we can go, but even 25-40% of electricity would be a huge contribution.
Combine that with the new and existing nuclear, another 15%, some biomass and tidal lagoons, with the rest from gas (which produces half as much CO2 as coal) and it will go a long way towards meeting the UK's 80% CO2 reduction target from 1990 to 2050.
[+] [-] kylegordon|8 years ago|reply
There's also various news articles reporting on German mines beginning to be used as pumped storage sites, with a reservoir on the surface, and water dropping into the mines below when there's sudden demand.
This is a good problem to have, though.
[+] [-] Gravityloss|8 years ago|reply
[+] [-] everyone|8 years ago|reply
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.
[+] [-] dmd|8 years ago|reply
[+] [-] dschuetz|8 years ago|reply
[+] [-] boxcardavin|8 years ago|reply
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 throttle is producing about .2 megawatts, so the worlds largest turbines are generating the same power as 10/.2=20 minivans at full power.
Another way to think of it is in terms of heat. A big stovetop burner will generate about 3000 watts of heat, so a minivan is like 65 burners at full blast, and a 10 megawatt turbine is like 3300 burners.
[+] [-] indescions_2018|8 years ago|reply
How to Buy a Wind Farm
https://www.bloomberg.com/news/articles/2018-04-23/the-puert...
[+] [-] dmix|8 years ago|reply
http://www.vortexbladeless.com/
Based on their marketing (far quieter, 40% more energy) it seems like an interesting option. I know one of the biggest complaints that farmers have is the noise they cause, so they have to be placed far from houses.
I'm curious to see if it's mostly fluff or has any potential... but I'm not expert on the subject.
[+] [-] andbberger|8 years ago|reply
[+] [-] cesarb|8 years ago|reply
South America too. In just the last 12 months, installed capacity in Brazil went from 10.4 GW to 12.5 GW (source: Boletim Mensal de Geração Eólica - ONS).
[+] [-] coryfklein|8 years ago|reply
[+] [-] cschmidt|8 years ago|reply
[+] [-] torpfactory|8 years ago|reply
[+] [-] konceptz|8 years ago|reply
[+] [-] uhnuhnuhn|8 years ago|reply
[+] [-] IAmEveryone|8 years ago|reply
[+] [-] reacharavindh|8 years ago|reply
I wish they focus as much on micro grids as much on energy generation.
[+] [-] jcun4128|8 years ago|reply
Those turbines appeared to have an upward inclination, curious why that is. Also interesting that the trailing edge near the hub isn't as sharp as the tips probably due to slowest rotation.
Good stuff, those things are seriously massive.
I also like that giant wall monitor with all the 'stats'?
[+] [-] w_t_payne|8 years ago|reply
https://www.asvglobal.com/
These little boats can continuously monitor the foundations of offshore wind turbines for scour, and their larger brethren can quickly deliver supplies in a wide range of weather conditions -- without putting human engineers at risk.
[+] [-] roncohen|8 years ago|reply
By the way, you can walk right up to them. They are very impressive up close.
[+] [-] jacquesm|8 years ago|reply
[+] [-] macmac|8 years ago|reply
[+] [-] mack1001|8 years ago|reply
[+] [-] unknown|8 years ago|reply
[deleted]
[+] [-] DoctorOetker|8 years ago|reply
[+] [-] eddieschod|8 years ago|reply
[+] [-] alphydan|8 years ago|reply
Money-shot on p66. About 8 months for EROEI (Energy returned on energy invested). I worked on some of these Life Cycle Analyses and can attest that they were quite rigorous.