3 ms·

So .. if we plot the electricity demand curve, baseline would be a level line going through the (weekly) bottom of the curve. Baseline power is below the line a

by labawi 5y ago

So .. if we plot the electricity demand curve, baseline would be a level line going through the (weekly) bottom of the curve. Baseline power is below the line and the rest is above, correct? Renewables and more specifically storage is not ready, so the part that is below base line is currently served by gas (and some coal/nuclear) and the part that is above is delivered by renewables without need for storage?

p_l 5y ago
Yes. Baseline is essentially the line below which demand doesn't drop. A problem with renewables is that they still need storage to work as peakers, because in many places renewable production doesn't happen in peak times.
- labawi 5y ago
  So, is below baseline powered by gas and coal? If so, why? Wouldn't it make more sense to cover as much as you can with renewables, including as much below and above the baseline, then cover the rest with gas for now and HVDC/storage/demand shifting/.. later? I.e. calculate demand - renewables. Cover that. Don't see the point of baseline.
  - Jensson 5y ago
    You do realize that every country is already doing what you are suggesting? The point however is that unreliable renewables doesn't cover anything at all reliably, so you need reliable power to cover 100% of demand or you will have regular blackouts. You can achieve that by having enough battery storage to fuel the whole country for months to last the whole winter, or you build reliable power plants like nuclear, coal or gas. We aren't even close to having the battery solution even within decades, so the only alternative are the unrenewable power plants. And no, betting on a good winter isn't a solution. If those batteries runs out and large swathes of the country blacks out for months during a cold winter many will die. That is not a good solution.
    - pfdietz 5y ago
      Using batteries to get renewables to 100% is bad systems engineering. It's cheaper to use something like hydrogen for the last 10-20%, and for seasonal load leveling.
    - labawi 5y ago
      Yes, they do. If you notice, you have mentioned baseload, baseload power generation, baseload demand or base-anything exactly 0 times, because it has near 0 relevance, which is the point of the entire discussion.
ashtonkem 5y ago
> So .. if we plot the electricity demand curve, baseline would be a level line going through the (weekly) bottom of the curve. Baseline power is below the line and the rest is above, correct? Correct. > the part that is below base line is currently served by gas (and some coal/nuclear) and the part that is above is delivered by renewables without need for storage? Pretty close, but a bit of an over simplification. Exactly what percentage of the grid is renewables at any given moment depends on the installed ("nameplate") capacity of various generation sources, and their mix. Even today it's not uncommon for the vast majority of a grid's demand to be met by renewables for short periods of time. The issue is that we can't do it reliably enough yet. Some sources of power are very slow to change their production (coal, nuclear), and therefore are designed to produce constantly[0]. If your grid has a lot of these, then your description above will be correct; your baseload plants will produce a constant level of power with renewables and imports handling demand spikes above that need. On the flip side, if your grid has a lot of natural gas or hydro, then you can spin these up and down to cover the difference between what your consumers want and what your renewables are creating (plus or minus big industrial loads that can be shed on demand). Batteries fit into this category, and theoretically a grid with a ton of batteries wouldn't need anything other than sufficient renewables and batteries to meet demand. Until such a time that we have enough batteries to make a fully renewable grid possible, your grid must have a mix of nuclear, coal, or natural gas[1] to keep the lights on. For a direct illustration, consider California's mix right now. If you read carefully you'll notice that nuclear and coal power remains extremely flat in CA (16MW and 1140MW or so respectively), while natural gas and unspecified imports tend to move in inverse correlation to the amount of power generated by renewables. If the renewable production were bigger, it possibly would have eclipsed demand mid day and enabled the export or shutdown of that Coal power. On the flip side you also have to note that currently solar power is dropping off in CA right as demand is spiking. A true renewable grid would need enough batteries to provide 26,000 MW of capacity or so for for hours, plus enough renewables to cover demand + charging. It's doable, but it'll take time. Also, right now CA is producing a mere 459MW worth of energy from its grid scale batteries, which is roughly 1/3rd of what CA's one nuclear power plant provides. They're planning on shutting this plant down, rather than building new ones. http://www.caiso.com/TodaysOutlook/Pages/supply.html http://www.caiso.com/TodaysOutlook/Pages/supply.html 0 - Confusingly these are called "baseload power plants". 1 - Or hydro, but that's really region dependent. The power coming from the utility company here is 42% Hydro, but that's because I live in a mountain state.

by labawi 5y ago

p_l 5y ago

Yes. Baseline is essentially the line below which demand doesn't drop. A problem with renewables is that they still need storage to work as peakers, because in many places renewable production doesn't happen in peak times.

labawi 5y ago
So, is below baseline powered by gas and coal? If so, why? Wouldn't it make more sense to cover as much as you can with renewables, including as much below and above the baseline, then cover the rest with gas for now and HVDC/storage/demand shifting/.. later? I.e. calculate demand - renewables. Cover that. Don't see the point of baseline.
- Jensson 5y ago
  You do realize that every country is already doing what you are suggesting? The point however is that unreliable renewables doesn't cover anything at all reliably, so you need reliable power to cover 100% of demand or you will have regular blackouts. You can achieve that by having enough battery storage to fuel the whole country for months to last the whole winter, or you build reliable power plants like nuclear, coal or gas. We aren't even close to having the battery solution even within decades, so the only alternative are the unrenewable power plants. And no, betting on a good winter isn't a solution. If those batteries runs out and large swathes of the country blacks out for months during a cold winter many will die. That is not a good solution.
  - pfdietz 5y ago
    Using batteries to get renewables to 100% is bad systems engineering. It's cheaper to use something like hydrogen for the last 10-20%, and for seasonal load leveling.
  - labawi 5y ago
    Yes, they do. If you notice, you have mentioned baseload, baseload power generation, baseload demand or base-anything exactly 0 times, because it has near 0 relevance, which is the point of the entire discussion.

ashtonkem 5y ago

> So .. if we plot the electricity demand curve, baseline would be a level line going through the (weekly) bottom of the curve. Baseline power is below the line and the rest is above, correct? Correct. > the part that is below base line is currently served by gas (and some coal/nuclear) and the part that is above is delivered by renewables without need for storage? Pretty close, but a bit of an over simplification. Exactly what percentage of the grid is renewables at any given moment depends on the installed ("nameplate") capacity of various generation sources, and their mix. Even today it's not uncommon for the vast majority of a grid's demand to be met by renewables for short periods of time. The issue is that we can't do it reliably enough yet. Some sources of power are very slow to change their production (coal, nuclear), and therefore are designed to produce constantly[0]. If your grid has a lot of these, then your description above will be correct; your baseload plants will produce a constant level of power with renewables and imports handling demand spikes above that need. On the flip side, if your grid has a lot of natural gas or hydro, then you can spin these up and down to cover the difference between what your consumers want and what your renewables are creating (plus or minus big industrial loads that can be shed on demand). Batteries fit into this category, and theoretically a grid with a ton of batteries wouldn't need anything other than sufficient renewables and batteries to meet demand. Until such a time that we have enough batteries to make a fully renewable grid possible, your grid must have a mix of nuclear, coal, or natural gas[1] to keep the lights on. For a direct illustration, consider California's mix right now. If you read carefully you'll notice that nuclear and coal power remains extremely flat in CA (16MW and 1140MW or so respectively), while natural gas and unspecified imports tend to move in inverse correlation to the amount of power generated by renewables. If the renewable production were bigger, it possibly would have eclipsed demand mid day and enabled the export or shutdown of that Coal power. On the flip side you also have to note that currently solar power is dropping off in CA right as demand is spiking. A true renewable grid would need enough batteries to provide 26,000 MW of capacity or so for for hours, plus enough renewables to cover demand + charging. It's doable, but it'll take time. Also, right now CA is producing a mere 459MW worth of energy from its grid scale batteries, which is roughly 1/3rd of what CA's one nuclear power plant provides. They're planning on shutting this plant down, rather than building new ones. http://www.caiso.com/TodaysOutlook/Pages/supply.html http://www.caiso.com/TodaysOutlook/Pages/supply.html 0 - Confusingly these are called "baseload power plants". 1 - Or hydro, but that's really region dependent. The power coming from the utility company here is 42% Hydro, but that's because I live in a mountain state.