Random EV thoughts.....

ELM327

September1 wrote: »

I think issue is that you would need to store energy for handle longer periods of no wind than single day, which I think is not something that can be economical with batteries for decades - as this kind of storage would be used handful times a year, and perhaps not at all on some years.

I think there must be some way to incorporate this - im not saying as a replacement for coal but to reduce reliance on coal. Reduce peak needed by generating at night and using that throughout the day

September1

ELM327 wrote: »

I think there must be some way to incorporate this - im not saying as a replacement for coal but to reduce reliance on coal. Reduce peak needed by generating at night and using that throughout the day

There are multiple problems with balancing electrical network, you seem to be focusing on daily peaks which are not only problem. For example battery in Australia which is one of most known projects is not dealing with that issue, as it charges and discharges multiple times a day. It helps to stabilize network by smoothing quick changes in supply and demand that happen throughout a day, like wind breeze becoming weaker for few minutes. This means that they could buy cheaper electricity and then sell it with profit multiple times per day, however I'm pretty sure that economics is more complicated and they also get some fixed fees as there is value in being available - however for simplicity lets assume that they get multiple sales of electricity per day. I think such battery would be profitable in most places right now with current technology.


Then there is a problem you mention about daily balancing of production and supply, which I guess requires only one cycle and provides only with one sale of energy per day. This kind of storage could be close to being profitable with current technology, but it may also make more sense economically to manufacture batteries for cars and sell then with higher premium. This problem can also be helped with smart meters, commercial freezers, EV charging and couple other ways to balance things on demand side.



The biggest problem is long-term balancing, where renewable sources are off for many days, such battery would be rarely needed so it will be difficult to make it profitable but then it would have much higher capacity then in other cases as it would have to power country for weeks.

Markcheese

Pumped electric storage is great, an amazing asset ,but effectively it's a battery ...great for short peaks and troughs ..there's another one in some stage of development in an old mine (Midlands maybe), but it doesn't seem to be progressing very fast ..

We're going to still need fossil fuels to back up wind ,batteries and interconnectors will reduce how much spinning reserve we need ... But to cover that dead calm,cold week in january that we get every few years it's going to need gas

Black_Knight

September1 wrote: »

https://www.breakingnews.ie/ireland/planning-permission-granted-for-controversial-energy-plant-in-roscommon-935133.html

Picked the wrong county to implement something progressive.

jprboy

Markcheese wrote: »

Pumped electric storage is great, an amazing asset ,but effectively it's a battery ...great for short peaks and troughs ..there's another one in some stage of development in an old mine (Midlands maybe), but it doesn't seem to be progressing very fast ..

Yep, proposed pumped hydro 360 MW in old mining site in Silvermines, Co. Tipp

https://silvermineshydro.ie/

unkel

ELM327 wrote: »

I think there must be some way to incorporate this - im not saying as a replacement for coal but to reduce reliance on coal.

Thankfully, Ireland pretty much stopped using coal for electricity generation nearly a year ago.

MJohnston

unkel wrote: »

Thankfully, Ireland pretty much stopped using coal for electricity generation nearly a year ago.

What about Moneypoint?

ELM327

unkel wrote: »

Thankfully, Ireland pretty much stopped using coal for electricity generation nearly a year ago.

Really?
http://smartgriddashboard.eirgrid.com/#roi/generation suggests otherwise

KCross

ELM327 wrote: »

Really?
http://smartgriddashboard.eirgrid.com/#roi/generation suggests otherwise

A year or more ago coal was consistently at about 15%.
https://www.boards.ie/vbulletin/showpost.php?p=111242744&postcount=319

Its now consistently <5% (at 3% for the last month) and had several months at 0% because the plant was offline for maintenance. Its close to being mothballed I'd say.

Officially its decommissioning date is 2025, I think.

ELM327

KCross wrote: »

A year or more ago coal was consistently at about 15%.
https://www.boards.ie/vbulletin/showpost.php?p=111242744&postcount=319

Its now consistently <5% (at 3% for the last month) and had several months at 0% because the plant was offline for maintenance. Its close to being mothballed I'd say.

Officially its decommissioning date is 2025, I think.

Interesting.


Also interesting is that we are at 1/3 renewable for MTD

KCross

ELM327 wrote: »

Interesting.


Also interesting is that we are at 1/3 renewable for MTD

Our yearly average for renewable is about 30% for a few years now.
They want to double that in the decade ahead!

Water John

A study in the UK out today, says it will need storage of 30GW which is 30% of peak demand when the system becomes carbon neutral. UK has 3GW at present.

Should be need for 2GW here, maybe a good bit more.

BTW as I suggested before, it says the cheapest electricity will be during day time, solar and wind combined, and biggest demand in the evening.

September1

Water John wrote: »

A study in the UK out today, says it will need storage of 30GW which is 30% of peak demand when the system becomes carbon neutral. UK has 3GW at present.

Should be need for 2GW here, maybe a good bit more.

I think UK has nuclear power, which is carbon neutral and solves may problems with renewable sources.

redcup342

A Company in Dusseldorf is rolling these out in Germany to cover areas where rapid charging could be useful but a bit investment is needed.

https://www.uniper.energy/services/move-by-uniper

Would be handy in parts of Ireland where the Infrastructure isn't there or to cover extra demand while they build new charging stations.

McGiver

jprboy wrote:

Yep, proposed pumped hydro 360 MW in old mining site in Silvermines, Co. Tipp

What's the efficiency of this thing? And EROEI?

Water John

Pumped storage has an 80% efficiency. The pump becomes the generator, same as an EV.

KCross

Water John wrote: »

Pumped storage has an 80% efficiency. The pump becomes the generator, same as an EV.

Are you sure?

I watched a documentary on it recently and they said the overall efficiency was pretty poor but it doesnt matter because the energy is "free" (i.e. renewables that would be otherwise curtailed) so its a net gain.... i thought the efficiency was something like 30% (or in that ball park anyway).

Obviously burning coal to run pumped hydro would be terrible but thats not the idea of it. Its there to simply capture some of the otherwise wasted renewable energy.

air

30%?
Turlough hill would be steaming like a volcanic vent after a few cycles
Edit It's 75% round trip according to it's wikipedia page. Not bad for an old installation

KCross

air wrote: »

30%?
Turlough hill would be steaming like a volcanic vent after a few cycles

I miss your point.
What do you mean?

air

KCross wrote: »

I miss your point.
What do you mean?

I meant that 30% would be ridiculously low efficiency.
The losses would generally be absorbed by the water primarily so you'd have ~100MW of heat being dissipated into it constantly if the true efficiency was 30%

samih

air wrote: »

I meant that 30% would be ridiculously low efficiency.
The losses would generally be absorbed by the water primarily so you'd have ~100MW of heat being dissipated into it constantly if the true efficiency was 30%

Would even be a bit higher as the plant is capable for up to 1.7 GWh of generation per cycle. You'd need to input upwards 5 GWh of power per 24h with 30 percent efficiency. If somebody knows the water volume it would be quite easy to estimate the temperature gain per cycle.

Edit: Answering to myself. I'm also not a matemathician so could well made an error with my calculations (as often is):

Water mass of the Turlough hill is about is 2.3x10^12 g. The water specific heat is 4.186 J/g*K and the power input of new new improved efficiency of 75% is 2.3 GWh which is 2.3*10^9 Wh that converts to 8.3*10^12 J.

This amount of energy increases the water temperature of Turlough hill reservoir by approx. 1'C per cycle which appears to be well within the cooling capacity of the natural radiation and convection etc. Even if the efficiency was only 30% the heating would only be about 1.8 degress which is way less than I thought and would not result Turlough hill turning into a cheap copy of a volcano anytime soon.

KCross

air wrote: »

I meant that 30% would be ridiculously low efficiency.
The losses would generally be absorbed by the water primarily so you'd have ~100MW of heat being dissipated into it constantly if the true efficiency was 30%

Fair enough. Must have remembered that wrong then.

Do you know what efficiency Turlough hill runs at?

EDIT: I see your edit.... 75%.

air

samih wrote: »

Would even be a bit higher as the plant is capable for up to 1.7 GWh of generation per cycle. You'd need to input upwards 5 GWh of power per 24h with 30 percent efficiency. If somebody knows the water volume it would be quite easy to estimate the temperature gain per cycle.

Easy calculate the flow rate with the nominal power (294MW), head (549m) & quoted one way efficiency (86.6%)

In any case it appears to be huge (ballpark 63m3/s) and the temperature rise is less than I expected at < 1 degree C each way even at the 30% round trip efficiency based on a back of the envelope analysis.

samih

More interesting maths for a slow Friday: The daily generating capacity of Turlough hill would allow ELM327 to fully charge his 90 kWh Model S 17000 times assuming efficiency of 90 percent. The net energy gain of 1.5 GWh would allow 6 million kilometers of driving per day at 250 Wh/km.

air

On a similar note I think I saw an ad for the Audi Etron with a wind turbine in the background.
They quoted 4 revolutions for a full charge or something similar, thought it was a nice touch!

Silent Running

I remember, as a lad, standing in the empty upper lake before it was commissioned. My father was one of the engineers on the project. An impressive bit of kit for the time.

Giving away my age here.

samih

Silent Running wrote: »

I remember, as a lad, standing in the empty upper lake before it was commissioned. My father was one of the engineers on the project. An impressive bit of kit for the time.

Giving away my age here.

The upper reservoir is still an impressive sight today. Back in 90's when I first arrived to Ireland the fence around it was in bad repair and I might have climbed up to take a look at it. It must have been really cool to work in a big infrastructure project like that. I'm still kicking myself as I missed the open days there last year.

Silent Running

samih wrote: »

The upper reservoir is still an impressive sight today. Back in 90's when I first arrived to Ireland the fence around it was in bad repair and I might have climbed up to take a look at it. It must have been really cool to work in a big infrastructure project like that. I'm still kicking myself as I missed the open days there last year.

Yeah, my father was involved in some great projects in his time. I remember he did a lot of work on the North/South electricity inter-connector, as well as the second Poolbeg stack.

unkel

air wrote: »

On a similar note I think I saw an ad for the Audi Etron with a wind turbine in the background.
They quoted 4 revolutions for a full charge or something similar, thought it was a nice touch!

Nice touch, let's do a reality check with some more slow Friday afternoon maths:

I didn't see the ad, but let's presume it's about the biggest off shore windmills that are currently producing, 10MW

These produce 10MWh/60 minutes = 167kWh/minute

With about 10 revs per minute, that's nearly 17kWh per rev, so about 67kWh per 4 revs, so yeah, the ad is pretty much on the ball

(if the wind generator in the ad was smaller, their claim would be exaggerated)

Dardania

unkel wrote: »

Nice touch, let's do a reality check with some more slow Friday afternoon maths:

I didn't see the ad, but let's presume it's about the biggest off shore windmills that are currently producing, 10MW

These produce 10MWh/60 minutes = 167kWh/minute

With about 10 revs per minute, that's nearly 17kWh per rev, so about 67kWh per 4 revs, so yeah, the ad is pretty much on the ball

(if the wind generator in the ad was smaller, their claim would be exaggerated)

*20-80%