5 ms·

Why can't existing energy infrastructure handle the gaps? Does it take too long to boot up a natural gas plant just for the night? Would still make a huge dent

by immad 8y ago

Why can't existing energy infrastructure handle the gaps? Does it take too long to boot up a natural gas plant just for the night? Would still make a huge dent to energy needs and the existing infrastructure already in place.

rock_hard 8y ago
Without a buffer (like a battery) solar energy fluctuates highly because of clouds and other things that get in the way for split seconds during the day.
- rtkwe 8y ago
  That seems like a point where distributed rooftop solar has a pretty good edge over utility solar (ie huge fields of solar cells). Spread over a large enough area all those tiny peaks and fluctuations will even out largely.
inputcoffee 8y ago
That is true, and existing infrastructure does (mostly) handle the gaps. How much does "existing infrastructure" charge to handle the gaps? This calculation differs wildly from as low as $6 to as high as $15, but I think $12 is the right answer. So add $12 to solar only as a rough rule of thumb. Note that this $12 still comes with transmission issues, and environmental impact.
rsynnott 8y ago
That's what's generally happening. It's a bit of a limiting factor, though. As you have more and more renewable, you need more and more gas plants which mostly sit around doing nothing, which isn't free. There's also the opposite problem, particularly in the case of wind turbines; if you have enough, then your base-load (ie coal, nuclear, hydro) plus renewable may sometimes exceed demand. This happens from time to time in Ireland, for instance, due to a large installed base of wind. At that point you have to turn off renewable, and that's not always trivial or instant. Storage would help there, too, by absorbing the excess.
- ghouse 8y ago
  > As you have more and more renewable, you need more and more gas plants This is only true if the load on the grid is growing. In North America, it is not. Otherwise, you already have enough dispatchable generation available when the sun isn't shining or the wind isn't blowing.
  - rsynnott 8y ago
    This is assuming that you're replacing old, bad power (ie coal, or old-fashioned unresponsive gas plants) with a solar/responsive gas turbine combo. The US still has a fair bit of coal that could stand to be replaced, but I doubt there's enough gas to take up the slack of a solar/gas system without building more.
    - ghouse 8y ago
      Over the past decade (since the wide-scale commercialization of fracking in the US), coal plants have been retired or repowered (with gas) at a record pace. I believe the share of generation has dropped from 50% to 30% in that period.
  - p1mrx 8y ago
    The North American grids will need to start growing again, if electric vehicles become common.
  - robocat 8y ago
    > This is only true if the load on the grid is growing. In North America, it is not. The article I saw the other day showed growth of 4.5% (comparing Q1 2017 with Q1 2018) Surely that growth in production is matched by a growth in load? https://renewablesnow.com/news/wind-solar-farms-produce-10-of-us-power-in-4-mo-617830/ https://renewablesnow.com/news/wind-solar-farms-produce-10-o...
    - toomuchtodo 8y ago
      > Surely that growth in production is matched by a growth in load? It is not, although consumption growth may trend upwards again as transportation is electrified (and oil consumption moves to electrical consumption). https://www.bloomberg.com/view/articles/2018-03-01/americans-electricity-use-just-keeps-falling https://www.bloomberg.com/view/articles/2018-03-01/americans...
coryfklein 8y ago
Because total load on the power grid peaks at 8 PM when solar is providing nearly 0% of the power [1]. This means that no matter how many additional solar panels you add to the system, you are not displacing a single fossil fuel plant. Sure it's good that those plants are running nominally fewer hours per day per additional solar panel, but the cost to own, operate, and maintain the panels is roughly constant. This results in the effect of increased prices for fossil power in a way that can't be offset by solar. [1] https://en.wikipedia.org/wiki/Duck_curve https://en.wikipedia.org/wiki/Duck_curve
- stale2002 8y ago
  Industrial usage makes up a large percentage of total energy usage. Industrial energy usage can be time shifted. Who cares about residential power, if it is a small percentage of total energy usage?

by immad 8y ago

rock_hard 8y ago

Without a buffer (like a battery) solar energy fluctuates highly because of clouds and other things that get in the way for split seconds during the day.

rtkwe 8y ago
That seems like a point where distributed rooftop solar has a pretty good edge over utility solar (ie huge fields of solar cells). Spread over a large enough area all those tiny peaks and fluctuations will even out largely.

inputcoffee 8y ago

That is true, and existing infrastructure does (mostly) handle the gaps. How much does "existing infrastructure" charge to handle the gaps? This calculation differs wildly from as low as $6 to as high as $15, but I think $12 is the right answer. So add $12 to solar only as a rough rule of thumb. Note that this $12 still comes with transmission issues, and environmental impact.

rsynnott 8y ago

That's what's generally happening. It's a bit of a limiting factor, though. As you have more and more renewable, you need more and more gas plants which mostly sit around doing nothing, which isn't free. There's also the opposite problem, particularly in the case of wind turbines; if you have enough, then your base-load (ie coal, nuclear, hydro) plus renewable may sometimes exceed demand. This happens from time to time in Ireland, for instance, due to a large installed base of wind. At that point you have to turn off renewable, and that's not always trivial or instant. Storage would help there, too, by absorbing the excess.

ghouse 8y ago
> As you have more and more renewable, you need more and more gas plants This is only true if the load on the grid is growing. In North America, it is not. Otherwise, you already have enough dispatchable generation available when the sun isn't shining or the wind isn't blowing.
- rsynnott 8y ago
  This is assuming that you're replacing old, bad power (ie coal, or old-fashioned unresponsive gas plants) with a solar/responsive gas turbine combo. The US still has a fair bit of coal that could stand to be replaced, but I doubt there's enough gas to take up the slack of a solar/gas system without building more.
  - ghouse 8y ago
    Over the past decade (since the wide-scale commercialization of fracking in the US), coal plants have been retired or repowered (with gas) at a record pace. I believe the share of generation has dropped from 50% to 30% in that period.
- p1mrx 8y ago
  The North American grids will need to start growing again, if electric vehicles become common.
- robocat 8y ago
  > This is only true if the load on the grid is growing. In North America, it is not. The article I saw the other day showed growth of 4.5% (comparing Q1 2017 with Q1 2018) Surely that growth in production is matched by a growth in load? https://renewablesnow.com/news/wind-solar-farms-produce-10-of-us-power-in-4-mo-617830/ https://renewablesnow.com/news/wind-solar-farms-produce-10-o...
  - toomuchtodo 8y ago
    > Surely that growth in production is matched by a growth in load? It is not, although consumption growth may trend upwards again as transportation is electrified (and oil consumption moves to electrical consumption). https://www.bloomberg.com/view/articles/2018-03-01/americans-electricity-use-just-keeps-falling https://www.bloomberg.com/view/articles/2018-03-01/americans...

coryfklein 8y ago

Because total load on the power grid peaks at 8 PM when solar is providing nearly 0% of the power [1]. This means that no matter how many additional solar panels you add to the system, you are not displacing a single fossil fuel plant. Sure it's good that those plants are running nominally fewer hours per day per additional solar panel, but the cost to own, operate, and maintain the panels is roughly constant. This results in the effect of increased prices for fossil power in a way that can't be offset by solar. [1] https://en.wikipedia.org/wiki/Duck_curve https://en.wikipedia.org/wiki/Duck_curve

stale2002 8y ago
Industrial usage makes up a large percentage of total energy usage. Industrial energy usage can be time shifted. Who cares about residential power, if it is a small percentage of total energy usage?