Germany pays for you to use electicity

[tszaboo]

http://qz.com/680661/germany-had-so-much-renewable-energy-on-sunday-that-it-had-to-pay-people-to-use-electricity/
The price of electricity went negative for a few hours, when renewable energy production went 87% of the demand. It was a windy day.
So I guess it is time for massive scale storage developments.

[depeje]

It was a windy day indeed, and sunny too. My tow plane pilot didn't dare to fly in this wind. (I got sunburn too, from being on the ground all day, rigging and de-rigging gliders.)

[tautech]

So I guess it is time for massive scale storage developments.

Magnetically levitated high speed flywheels 

[DenzilPenberthy]

It's also time to have some sensible discussion about demand-side management.  The technology is really easy to allow more flexible pricing to domestic consumers, but (certainly here in the UK) the only tariffs you can get are fixed rate 24/7 or slightly more expensive during the day and cheaper at night.

When the suppliers make some smart tariffs that are flexible, I think we'll see the demand more closely follow the supply. I'd happily put four loads of laundry on and put the immersion heater on if the price went super low for a few hours.


Also: more interconnectors!  The UK could have bought 5GW of that surplus power if there was infrastructure to transmit it.

[Delta]

This has been the case for quite a while now.

It's the obvious result of adding more and more intermittent renewables to a grid without adding any large scale storage.  Not only does it result in the price going negative, but fossil fuelled plants have to run more and more outside their optimum load points, causing a significant drops in efficiency and increases in emissions.

Activists and politicians like to shout about building more wind farms and solar arrays, but you never hear anyone talking about building storage.  It's just not exciting enough... 

[station240]

If I recall there was also a news story for one of the southern US states where power was free at certain times, due to all the wind/solar output.
Was it Texas ?

This is an example where a internet linked system in every home would be an advantage.
If there is an excess of power (especially renewable power), then increase demand.

For instance, set the electric car to recharge, home battery storage, hotwater heater.
If an aircon is running but the thermostat has switched the compressor out, bypass the thermostat for a brief period.

Problem is it needs to be selective, as turning everything on would blow fuses. So you have priorities:
1. Energy storage built without a renewable power input (no solar panels, wind etc).
2. Electric cars (but beware of high power draw).
3. Heating/Cooling (minor changes to operation).
Fun and games start when you compare start up times, Power Factor etc of various devices.
If you have a short spike in demand/price (up or down), then anything with a relay may not be fast enough.

So you need highspeed, low latency network connections to do this. *
As you need to be able to switch rapidly to avoid making the grid unstable.
Which means fibre, I know Germany does have a lot of VDSL over copper lines.

*Rules out Australia as we are currently building a shitty non fibre based broadband network, due to corrupt politicians.

[bitslice]

When the suppliers make some smart tariffs that are flexible, I think we'll see the demand more closely follow the supply. I'd happily put four loads of laundry on and put the immersion heater on if the price went super low for a few hours.

We'll need to bring back dumb washing machines first,
if I put mine on a timer to run overnight, it will happily sit there waiting for someone to press the start button 

[Someone]

It's the obvious result of adding more and more intermittent renewables to a grid without adding any large scale storage.  Not only does it result in the price going negative, but fossil fuelled plants have to run more and more outside their optimum load points, causing a significant drops in efficiency and increases in emissions.

Wha wha wha, there is a competitor in town to the entrenched power suppliers. Also that should be:

increases in emissions per unit of energy produced

If you're throttling back inefficient plants due to an excess of energy supply (which is largely predictable in advance) they'll produce less pollution.

[Ice-Tea]

http://qz.com/680661/germany-had-so-much-renewable-energy-on-sunday-that-it-had-to-pay-people-to-use-electricity/
The price of electricity went negative for a few hours, when renewable energy production went 87% of the demand. It was a windy day.
So I guess it is time for massive scale storage developments.

Luckily the renewable plants don't have a fixed price for their energy with the delta payed by the government (us). #ohnowait

Luckily we don't have a new energy minister who seems to believe we just have to chuck all rooftops full of PV's because that's an investment that makes sense even without government interference (sic).

[FrankBuss]

I understand that a nuclear or coal plant can't be shut down fast, but why do they pay to feed energy to the grid? Doesn't look too difficult for me to get rid of too much energy for a short time, like heating a sea or underground. And here Wikipedia says that modern nuclear reactors can follow the load anyway.

[DenzilPenberthy]

because if the price is still positive there is no incentive at all for plants to not feed their excess power in to the grid. 

[Kilrah]

We'll need to bring back dumb washing machines first,
if I put mine on a timer to run overnight, it will happily sit there waiting for someone to press the start button 

Don't all current machines have a built-in delayed start feature already?

[zapta]

because if the price is still positive there is no incentive at all for plants to not feed their excess power in to the grid.

Everybody gets paid. Isn't it wonderful?

[MikeW]

We'll need to bring back dumb washing machines first,
if I put mine on a timer to run overnight, it will happily sit there waiting for someone to press the start button 

Don't all current machines have a built-in delayed start feature already?

Not only that once started and the door locks, every washing machine I have ever used insists on finishing the cycle. So you could press start, cut the power and when the power comes back on it will resume (maybe).

[DenzilPenberthy]

because if the price is still positive there is no incentive at all for plants to not feed their excess power in to the grid.

Everybody gets paid. Isn't it wonderful?

No because supply has to match demand. The only way to incentivise people to not feed power into an oversupplied grid is to make the price negative.
I don't really get what point you're trying to make...

[elgonzo]

We'll need to bring back dumb washing machines first,
if I put mine on a timer to run overnight, it will happily sit there waiting for someone to press the start button 

Don't all current machines have a built-in delayed start feature already?

Not only that once started and the door locks, every washing machine I have ever used insists on finishing the cycle. So you could press start, cut the power and when the power comes back on it will resume (maybe).

The few fully electronic washing machines i used in my life only exhibit such "resume" behavior if it has been switched off for a short time. After being switched off for a longer time (i can't tell from memory how long this "longer time" would be; but it certainly was longer than just a few minutes), the washing machine has been reset. Iirc, even my front loaders would unlock the door no matter whether there was still water in the drum or not; although there is a chance i remembered this bit incorrectly...
Old electro-mechanical machines are more likely matching your description: When a power cut occurs, the program wheel stops and remains at the position, only to continue the program as soon as power is being restored (with the help of a button press perhaps)...

[zapta]

because if the price is still positive there is no incentive at all for plants to not feed their excess power in to the grid.

Everybody gets paid. Isn't it wonderful?

No because supply has to match demand. The only way to incentivise people to not feed power into an oversupplied grid is to make the price negative.
I don't really get what point you're trying to make...

My point is that it's wonderful that at the same time some people are paid to feed the grid while others are paid to consume from the grid. It's a win/win.   

[DenzilPenberthy]

My point is that it's wonderful that at the same time some people are paid to feed the grid while others are paid to consume from the grid. It's a win/win.   

Well yep. That's how you incentivise non polluting resources to generate and polluting ones to not generate. It's not as bonkers as it seems.

[Red Squirrel]

Meanwhile here in Ontario when we produce excess they pay the US to use it, and charge us more! 

[Kleinstein]

The negative (wholesale) price occurs a few times a year for a short time. Sometimes they turn on some street light to get rid of excess (under the control of the energy companies). But this is only really short time, so no big incentive yet to invest much money because of this.

For large use costumers (e.g. industry, large cooling facilities) there are already supply dependent prices. So the use of power is adjusted by the supply situation - usually its not that much the few times of over-supply, but more to avoid extra load in times where supply is rather low or peak loads. So you can get an extra discount if you accept to run only at times the energy company likes it. I would guess this might get used more, even if this means higher investment costs.

For the consumers the power is relatively low, so the costs for controlling it might be to high. Even the washing machine is running only a few times a week, so not that much energy to shift around.

There are a few new build storage facilities, but not that many and not that large.

They also may need some of the generators in conventional power plants running to have the possibility to control the frequency and blind power.

[Red Squirrel]

Come to think of it how does the grid manage to supply the exact amount of power needed at any given instant, as I'm sure that changes from minute to minute, do most power plants have a decently wide range they can operate at just naturally? Like I imagine the turbines have so much momentum in them that the demand fluctuations arn't really a big deal until they are sustained or too big?

[Macbeth]

When the suppliers make some smart tariffs that are flexible, I think we'll see the demand more closely follow the supply. I'd happily put four loads of laundry on and put the immersion heater on if the price went super low for a few hours.

We'll need to bring back dumb washing machines first,
if I put mine on a timer to run overnight, it will happily sit there waiting for someone to press the start button 

Get with the times. I recently dumped an old Hotpoint despite my years of maintenance including replacing the drum bearings (what a hell of a fucking job!) and upgrading its shitty deliberately designed to break shock absorbers. A few solenoid tap changes and one pump. A couple of door seals too.

The new "super eco-friendly+++" model has a timed start mode, so you can delay it all you please. It was also far cheaper than fixing an extremely hard to find fault betwixt the control panel and the motor that insisted on smashing the machine against all the cupboards and trying its best to self destruct. I actually took this one down to the Atmel controller and was messing about with live mains and decided the time has come to downgrade to a modern one.

[DenzilPenberthy]

Come to think of it how does the grid manage to supply the exact amount of power needed at any given instant, as I'm sure that changes from minute to minute, do most power plants have a decently wide range they can operate at just naturally? Like I imagine the turbines have so much momentum in them that the demand fluctuations arn't really a big deal until they are sustained or too big?

Basically there's a very stressed out person in front of a big control panel switching generators on and off to keep the system running at 50Hz.  It's a much bigger problem here in the UK because we all get up at the end of popular TV programmes and put on the kitchen light, put on the electric kettle to make a tea and flush the toilet (water pumps turn on).  It means we get really big demand spikes.



I think the longer term fluctuations are dealt with by market pricing of wholesale electricity which incentivise people to either feed in or not as required.

You're correct that the system inertia really helps with short term stability but it's becoming less as we move away from large steam plant towards renewables.  See my thread here about what is being done about that:

https://www.eevblog.com/forum/renewable-energy/it's-happening-the-power-grid-is-changing/

[tszaboo]

Come to think of it how does the grid manage to supply the exact amount of power needed at any given instant, as I'm sure that changes from minute to minute, do most power plants have a decently wide range they can operate at just naturally? Like I imagine the turbines have so much momentum in them that the demand fluctuations arn't really a big deal until they are sustained or too big?

Like the turbines in the power plants are not only producers, but also consumers. And the grid changes frequency, so with lower frequency the load is less. And the voltage is fluctuating, so with more voltage the load is more. Off the top of my head. Ask an electrical engineer.

[Kleinstein]

The large rotating generators help to stabilize the grid frequency. It also helps that the grid is connected from Portugal to Poland / Finnland (AFAIK). So even if there is short time to much demand in the UK, they could use extra capacity from France, Italy or Spain. Here however the capacity of the lines is limited, even if the power is not really going that long distance, but just shifts a little.  At least in Germany they start to increase the allowed power limits to the lines - so much as allowing higher power if there is more wind for cooling.