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Bogus numbers: Wind and solar are always portrayed using "nameplate" capacity; their full theoretical capacity under ideal conditions, which rarely happens. (Th

Bogus numbers: Wind and solar are always portrayed using "nameplate" capacity; their full theoretical capacity under ideal conditions, which rarely happens. (They generally have no control over this, either.) On the other hand, something like a natural gas plant can usually produce at its full capacity pretty much on demand, although it probably only does this on relatively rare occasions, too. To use a local example, I have a solar plant nearby which is rated at one megawatt "nameplate". But for whatever reasons it is currently maxing out at only 60% of that, even under ideal conditions. And it looks like its average output may be as low as 17%, depending on how you count things. (I generally use 25% as a round, ballpark figure for wind and solar, although it looks like off-shore wind power at least is generally running much higher than that.) Wishful thinking: The wind and solar folks like to pretend that with enough storage (battery, pumped hydro, and so on ) then these can be as reliable and productive as more traditional power sources. Except that the storage stuff only has limited capacity, and is remarkably limited in many cases (to hours of capacity if not just minutes), so they're going to need something much more robust for backup. And that's generally means that the traditional sources will still be needed to fulfill this role. Which may be mostly fine technologically, but economically it will be quite expensive, and you need to include that added expense in the overall costs for wind and solar. It is wishful thinking to just ignore these factors. Google, which was quite into renewals themselves a while back, long ago stated that it was obvious that these were never really going to work out for them. Given that Google has pretty much unlimited intellectual and financial resources (or at least it did at the time), if there was anybody who could make this work it would probably be them. But apparently not so much.

Dylan16807 7y ago
Who are you talking to? The subject here was a study about reducing CO2 emissions by a certain amount. The "capacity" numbers weren't mentioned at all. The study's focus on how to reduce storage needs is the opposite of ignoring storage cost. Backup power isn't ignored either.
- southern_cross 7y ago
  The NOAA study being referenced is the one linked to below, from what I can tell. I mentioned that it was probably full of bogus numbers and wishful thinking, like many other similar studies I've seen, and you responded to that, and I responded to you with more details. Sorry if there was any confusion here. http://www.tresamigasllc.com/docs/nclimate2921.pdf http://www.tresamigasllc.com/docs/nclimate2921.pdf A quick read of it suggests the following limitations, among others; take the time to read it for yourself if you like: 1. It seems predicated on the notion that we can have a system where any shortfall in one part of the country can be easily made up for just by using the excess generation in other parts of the country. This appears to be a rather "blue sky" assumption to make, and one that I personally wouldn't be willing to make. 2. For the numbers quoted, it makes no mention of "nameplate" capacity vs. actual average capacity, which of course makes a huge difference as to the item above. 3. It makes the rather bizarre statement that HVAC lines can't transmit power over long distances, which clearly isn't true. (They can stretch for thousands of miles if need be, although most aren't anywhere near that long.) It may be true, though, that with current technology HVDC lines can transmit power more efficiently and for longer distances than HVAC lines can. 4. If I'm reading it correctly, it admits to not taking short term variability (an hour or less) into account, when such variability can be substantial. I may be reading it wrong, though. And so on. So at best this study can be taken as an example of out-of-the-box, non-traditional thinking, and perhaps as an encouragement for doing more of the same. But it hardly qualifies as any kind of proof that what they describe is technologically or economically feasible.

Dylan16807 7y ago

Who are you talking to? The subject here was a study about reducing CO2 emissions by a certain amount. The "capacity" numbers weren't mentioned at all. The study's focus on how to reduce storage needs is the opposite of ignoring storage cost. Backup power isn't ignored either.

southern_cross 7y ago
The NOAA study being referenced is the one linked to below, from what I can tell. I mentioned that it was probably full of bogus numbers and wishful thinking, like many other similar studies I've seen, and you responded to that, and I responded to you with more details. Sorry if there was any confusion here. http://www.tresamigasllc.com/docs/nclimate2921.pdf http://www.tresamigasllc.com/docs/nclimate2921.pdf A quick read of it suggests the following limitations, among others; take the time to read it for yourself if you like: 1. It seems predicated on the notion that we can have a system where any shortfall in one part of the country can be easily made up for just by using the excess generation in other parts of the country. This appears to be a rather "blue sky" assumption to make, and one that I personally wouldn't be willing to make. 2. For the numbers quoted, it makes no mention of "nameplate" capacity vs. actual average capacity, which of course makes a huge difference as to the item above. 3. It makes the rather bizarre statement that HVAC lines can't transmit power over long distances, which clearly isn't true. (They can stretch for thousands of miles if need be, although most aren't anywhere near that long.) It may be true, though, that with current technology HVDC lines can transmit power more efficiently and for longer distances than HVAC lines can. 4. If I'm reading it correctly, it admits to not taking short term variability (an hour or less) into account, when such variability can be substantial. I may be reading it wrong, though. And so on. So at best this study can be taken as an example of out-of-the-box, non-traditional thinking, and perhaps as an encouragement for doing more of the same. But it hardly qualifies as any kind of proof that what they describe is technologically or economically feasible.