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Jay McKinsey

New Aussie "big batteries"

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4 hours ago, eNiro said:

Renewables plus grid scale batteries kill gas peaking plants whenever they are installed. The Hornsdale Power Reserve in South Australia only has 2% of the grid capacity (as a generator) but has over 50% of the peaking market. It is first in the queue for frequency stabilising services and rightly so. There are similar projects like this cropping up all over the world which will eat into gas use for generating electricity, an incredibly wasteful process.

the following statements are all valid:

  • Gas peakers are wasteful and batteries can greatly reduce or eliminate them.
  • CCGTs are a lot less wasteful but cannot do peaking.
  • Renewables provide very cost-effective electricity
  • Renewable electricity is not always there when you need it
  • Batteries provide cost-effective short-term energy storage
  • Batteries cannot provide mid-term (weekly) or long-term (seasonal) storage
  • Today's systems use NG for mid and long term storage.

Arguing about any one of these statements misses the point. The system as a whole works today and we want it to work as well or better in the future. Many of us believe that fossil fuels cause global warming and must be eliminated. The challenge is to design and implement a transition from our current system to a system that does not use fossil fuels. The key word is "transition". It is cost-prohibitive to build an entirely new system in parallel with the existing system.

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Mr. Clemmensen 

The above statement "CCGTs ... cannot do peaking" is not quite correct.

Starting with the core hardware - aeroderivative gas turbines - one has the basic component of a 'gas peaker'.  From ignition to 100% capacity takes about 10 minutes.

The size of these turbines commonly considered for 'peaking' use varies depending upon the market, but it is not unusual to be in the 30 to 200 Mw range.

The same turbines - only usually  much larger - are used in CCGPs when downstream heat capture is used to heat steam turbine generators. (One example, Tasmania's plant uses a 140 Mw gas turbine with a 70 Mw steam turbine downstream. These are alongside 3 open cycle - pure 'peakers' - with 40 Mw capacity each).

The newest aeroderivative turbines run up to ~400 Mw with 50 Hz having a 571 Mw model.

 

Main point being, Mr. Clemmensen, that these large turbines act BOTH in baseload and peaker applications as the EIA itself highlights when describing the 'blurring' of traditional roles in this arena.

 

Come 1530 on a hot summer day - with grid operators pricing/managing power input in 5 minute increments - a CCGP operator may fire up a ~400 Mw turbine and have it at 100% in 10 minutes.

As the grid demand increases, the downstream steam generator may start to contribute some of its available ~200 Mw potential.

As the grid demand continues to increases come the 1800 hour, a second ~400 Mw aeroderivative turbine might fire up.

Some plants 'share' the downstream steam generators with the aeroderivative turbines, some have a dedicated steamer for each gas turbine.

 

2 main factors highlight the efficiencies of this technology ...

1. The plants can be ramped up very quickly (in peaker-type fashion) to produce on-demand power

2. When grid demand is highest, the sold electricity  is also the MOST expensive to the utilities who purchase it. This translates into higher revenues, hour per hour, to the CCGP owners.

Furthermore, in the 'slow hours' of 1000 to 1500, and 2000 to 0600, no fuel is burned which is a HUGE operational savings as all those LCOE/LACE analyses show.

(In contrast, solar tapers off just as late afternoon demand ramps up. Monitor CA ISO the next few days. Likewise, virtually all maximal wind power comes in the night time slow period, especially the lower demand winter time).

 

These are the main technical reasons why this technology is rapidly spreading all accross the globe, including many far flung locales as Gas To Power (LNG/FSRUs) is enabling power accessibility where it was previously deemed unthinkable.

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On 5/26/2020 at 12:43 PM, 0R0 said:

That is a very good idea. Much better than the renewables themselves, and has been adopted already in some areas by gas (and coal) plants to allow them to drop the spinning while still remaining a reserve, as they need only use the battery power to get their equipment started - within minutes, instead of operating on idle all the time. It makes CCGT  far cheaper to run as a reserve for part time operation as surge and in fill capacity. It also makes excess renewables capacity that much less attractive so long as gas can be cheap, as by definition, the excess capacity has no immediate economic value except to charge up storage.

I completely agree. But of course that natural gas will be green gas made from green hydrogen.

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21 hours ago, Dan Clemmensen said:

You don't have a larger need for "spinning reserve", which is sized to match the largest reasonable sudden supply loss.

You most certainly do for wind, depending on the level of penetration. I discuss this in other posts but for small levels of wind - perhaps even up to 10 per cent - maybe you don't need much in comparison with the amount supplied. The problem is that  when you get to levels like 30-40 per cent that becomes the large generator you talk about - you have to back up the bulk of it with spinning reserve. End of story. Then you also need spinning reserve for the largest generator in the conventional supply part.. Activists often try to argue that wind is supplied by a lot of small generators and if you spread them out, they don't all go down at once. The problem is that there is now considerable operational experience with wind generators and no-one has made that work. What they have discovered - and this wasn't really appreciated before the advent of large-scale wind generation - is that when wind goes down it does so over a very wide area. The problem is particularly acute in Europe, although less so in Australia. Dunno about the US. Batteries may help this but at considerable additional cost, of course. About the only other proposal I've heard which may reduce the problem is of DC lines connecting different areas over very wide distances. This is also very costly. Free wind energy is not cheap.. PVs and solar doesn't help much either.

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2 minutes ago, markslawson said:

You most certainly do for wind, depending on the level of penetration. I discuss this in other posts but for small levels of wind - perhaps even up to 10 per cent - maybe you don't need much in comparison with the amount supplied. The problem is that  when you get to levels like 30-40 per cent that becomes the large generator you talk about - you have to back up the bulk of it with spinning reserve. End of story. Then you also need spinning reserve for the largest generator in the conventional supply part.. Activists often try to argue that wind is supplied by a lot of small generators and if you spread them out, they don't all go down at once. The problem is that there is now considerable operational experience with wind generators and no-one has made that work. What they have discovered - and this wasn't really appreciated before the advent of large-scale wind generation - is that when wind goes down it does so over a very wide area. The problem is particularly acute in Europe, although less so in Australia. Dunno about the US. Batteries may help this but at considerable additional cost, of course. About the only other proposal I've heard which may reduce the problem is of DC lines connecting different areas over very wide distances. This is also very costly. Free wind energy is not cheap.. PVs and solar doesn't help much either.

I see your point. Since wind is subject to abrupt large-scale "failure", you need batteries to provide short-term replacement (equivalent to spinning reserve), just as you say, to the extent that you are counting on those wind turbines for instantaneous electricity. The batteries must carry the load until you can bring up your backup generators. But by the time we are nearing 100% renewable, the wind farms are part of an integrated system that includes CCGTs that are used when solar and PV are unavailable and the batteries have been emptied. These CCGTs consume gas (H2 or CH4) that is produced and stored when the there is excess PV and wind.

In an area that has a winter season, there will be times perhaps lasting a week or more when there is effectively no wind and no solar, and you are running on 100% CCGT plus battery peaking. The system must be sized for this, so you are eating that entire capital cost (pretty much equivalent to today's capital cost) But the plants run at far below capacity for most of the day for most of the year while PV and wind is available, and excess electricity is used to produce and store gas.

"Very costly" is a relative term. In the above scenario, the entire solar and wind investment does nothing to reduce capital cost: it is there only to reduce the amount of NG being consumed. This is not cost-effective in today's market when NG's price is artificially reduced by the surplus production of "associated" NG from oil wells. It becomes cost-effective as the cost of NG goes up as oil production goes down (especially in the Permian) and as the cost of gas from renewable electricity comes down due to technological advances and due to economies of scale. I don't know if these costs will ever cross over, but they are on the same order of magnitude.

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2 hours ago, Dan Clemmensen said:

I see your point. Since wind is subject to abrupt large-scale "failure", you need batteries to provide short-term replacement (equivalent to spinning reserve), just as you say, to the extent that you are counting on those wind turbines for instantaneous electricity. The batteries must carry the load until you can bring up your backup generators. But by the time we are nearing 100% renewable, the wind farms are part of an integrated system that includes CCGTs that are used when solar and PV are unavailable and the batteries have been emptied. These CCGTs consume gas (H2 or CH4) that is produced and stored when the there is excess PV and wind.

In an area that has a winter season, there will be times perhaps lasting a week or more when there is effectively no wind and no solar, and you are running on 100% CCGT plus battery peaking. The system must be sized for this, so you are eating that entire capital cost (pretty much equivalent to today's capital cost) But the plants run at far below capacity for most of the day for most of the year while PV and wind is available, and excess electricity is used to produce and store gas.

"Very costly" is a relative term. In the above scenario, the entire solar and wind investment does nothing to reduce capital cost: it is there only to reduce the amount of NG being consumed. This is not cost-effective in today's market when NG's price is artificially reduced by the surplus production of "associated" NG from oil wells. It becomes cost-effective as the cost of NG goes up as oil production goes down (especially in the Permian) and as the cost of gas from renewable electricity comes down due to technological advances and due to economies of scale. I don't know if these costs will ever cross over, but they are on the same order of magnitude.

It is doable, as you say, but the batteries are not there to fill in the holes in wind supply, they are there to get the gas turbines and coal plants started without having to spin on idle. The capital cost of Wind  is an order of magnitude higher than CCGT. Solar is far higher as well. But that does not consider how the rest of the grid operates because of this. When you finally do have the extra headroom for producing CH4, you will find that you spent 20X more on the system than the CCGT process would have cost you. And maintaining it will not be that cheap. 

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10 hours ago, Coffeeguyzz said:

Mr. Clemmensen 

The above statement "CCGTs ... cannot do peaking" is not quite correct.

 

Based on your post, I think you are being kind, here. I was totally wrong. Thanks for your explanation.

I will now make a leap from this to assume a CCGT can also act as spinning reserve.

I had already (implictly) assumed that when peaking (and also when compensating for sudden supply failure), efficiency is not important, since you are producing very high-value electricity.

Given these considerations, a system with renewables, batteries, and CCGTs looks technically feasible without the need for separate dedicated peakers or spinning reserve. Whether or not such a system makes economic sense is a different issue.

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53 minutes ago, 0R0 said:

It is doable, as you say, but the batteries are not there to fill in the holes in wind supply, they are there to get the gas turbines and coal plants started without having to spin on idle. The capital cost of Wind  is an order of magnitude higher than CCGT. Solar is far higher as well. But that does not consider how the rest of the grid operates because of this. When you finally do have the extra headroom for producing CH4, you will find that you spent 20X more on the system than the CCGT process would have cost you. And maintaining it will not be that cheap. 

I agree: you can ignore the renewables and evaluate the batteries as cost-saving adjuncts to a pure CCGT system. My new insight (which you guys already knew) is that since the system must be able to operate for one continuous week a year with no renewables, the non-renewable portion of the system will have effectively the same capital cost as a system with no renewables at all, and the capital cost of the renewables must then be added.

However, it turns out that you can evaluate the renewables solely as resources to produce gas. I did a trivial and probably incorrect analysis comparing the cost of a natural gas well in the Marcellus with the cost of a wind farm that produces the same amount of gas over a 30-year period. Making all sorts of assumptions, the two are similar. With the full CCGT system and its supporting gas storage and transport infrastructure in place, and the full renewables-to-gas infrastructure in place, you can then save a lot of gas on a daily and yearly basis by using the renewable electricity directly whenever possible instead of converting it to gas.  Let's say electricity==>electricity is 90% efficient, electricity==>gas==>electricity is 45% efficient, and the renewables+batteries operate 50% of the time.  You only need 2/3 of the renewables that you would need if you converted all the renewable electricity to gas.

This is all idle amateur speculation on my part and should be ignored until a proper analysis is done.

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5 minutes ago, Dan Clemmensen said:

I agree: you can ignore the renewables and evaluate the batteries as cost-saving adjuncts to a pure CCGT system. My new insight (which you guys already knew) is that since the system must be able to operate for one continuous week a year with no renewables, the non-renewable portion of the system will have effectively the same capital cost as a system with no renewables at all, and the capital cost of the renewables must then be added.

However, it turns out that you can evaluate the renewables solely as resources to produce gas. I did a trivial and probably incorrect analysis comparing the cost of a natural gas well in the Marcellus with the cost of a wind farm that produces the same amount of gas over a 30-year period. Making all sorts of assumptions, the two are similar. With the full CCGT system and its supporting gas storage and transport infrastructure in place, and the full renewables-to-gas infrastructure in place, you can then save a lot of gas on a daily and yearly basis by using the renewable electricity directly whenever possible instead of converting it to gas.  Let's say electricity==>electricity is 90% efficient, electricity==>gas==>electricity is 45% efficient, and the renewables+batteries operate 50% of the time.  You only need 2/3 of the renewables that you would need if you converted all the renewable electricity to gas.

This is all idle amateur speculation on my part and should be ignored until a proper analysis is done.

Te problem is that it isn't one week a year, it is several and spread out through the year with some periods, as in a typical German winter where both PV and wind are out. The all PV wind and battery system looks good on paper but is an enormous capital investment vs. CCGT. So with the exception of particular wind corridors and solar hot spots like the US SW, all renewables with batteries and CH4 production is still a long way from practical. Transmission is possible from the SW to the MidWest but rather lossy from there to the NE because of the need to run it in AC because of the high population density.

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6 minutes ago, 0R0 said:

Te problem is that it isn't one week a year, it is several and spread out through the year with some periods, as in a typical German winter where both PV and wind are out. The all PV wind and battery system looks good on paper but is an enormous capital investment vs. CCGT. So with the exception of particular wind corridors and solar hot spots like the US SW, all renewables with batteries and CH4 production is still a long way from practical. Transmission is possible from the SW to the MidWest but rather lossy from there to the NE because of the need to run it in AC because of the high population density.

I know its not just one week a year. I was trying to say that IF there is at least one week in which you have no renewables, THEN you need to be able to depend exclusively on the CCGTs for 100% of your power: no magic bridging or mystical cheating. Since you are forced to have this full up infrastructure for that week, you have it for any number of periods of any length of time.

Yes we are a long way from 100% non-fossil gas, but if we build renewable==>CH4, then we can build it anywhere in the world. We already have infrastructure to move CH4 from anywhere to anywhere. We are currently burning Permian gas in Europe and Australian gas in China. Texas has much more wind power than any other state, and Texas is already sending NG to Europe, so electricity==>gas in Texas may already make sense. Or not: it depends on the numbers, of course.  We also already know that if we are doing electricity to gas, we should first satisfy the demand for H2 and then satisfy the demand for NH3 before we start in on the demand for CH4. The beauty of electricity==>CH4 is that it can be done incrementally, one wind farm or one solar array at a time, with each one plugging into the existing CH4 collector system the way a new NG well does today.

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(edited)

You staunch advocates for Renewable Energy (sic) for electricity generation could be getting a real time, real world education in these matters if you keep an eye on California's ISO site (CA ISO Supply page).

Yesterday afternoon, nat gas supplied ramped from ~4Gw to ~17 Gw after the sun went down.

(The Blanche Dubois contributions were also significant).

Today, just past noon, couple of clouds or sumptin' musta floated by as solar started downward dip.

Not to worry.

Natgas racing to rescue with quick ramp from 5 to 9 Gw.

Ol' Zephyr completely collapsed to near nuttin'.

This stuff is so 18th century.

Edited by Coffeeguyzz

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On 5/28/2020 at 11:15 AM, Dan Clemmensen said:

I see your point. Since wind is subject to abrupt large-scale "failure", you need batteries to provide short-term replacement (equivalent to spinning reserve), just as you say, to the extent that you are counting on those wind turbines for instantaneous electricity.

Jut as a further note on this to round this issue out. From the articles cited at the beginning of this thread, it is apparent that regulatory authorities in the Northern Territory now require renewable energy projects to also include batteries capable of maintaining the output of the project for may be half and hour or so. That gives the grid managers time to ramp up conventional capacity and means far less spinning reserve, but at much greater cost, of course..  anyway, thanks for that ..leave it with out.. 

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It all comes down to politics. I can remember that the despicable Harold Wilson,when Labour Party Prime Minister of the UK in the 1960's,agreed to the demands of the National Union of Mineworkers that coal mining be subsidised by the Treasury and that coal-fired power stations be built to consume the poor quality (high ash) output. The UK Labour Party is now trying to get on the green bandwagon.

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