Study Shows Way to Power Grid with Solar and Renewables

[inetdog]

Maybe if Germany kept their Nuclear generation systems they would have the base needed to support their RE systems.

The base generating capacity has to be able to ramp its output up and down rapidly. Nuclear does not do that. I believe it is even worse in that way than coal, but I may be mistaken on that.
Gas turbines are among the fastest reacting, but they often cost more per Kwh, and still are not instantaneous. So you have to have both base load capability and peaker capability.

As RE goes, large Hydro is very stable over the day and can be ramped up and down fairly quickly, but the inertia of the water in the penstocks and other feed pipes has to be taken into account.
Micro hydro is vey stable and can be made quickly adjustable (although few can justify doing it) and wind will hopefully average out over a wide area and time of day.

[SunEagle]

The base generating capacity has to be able to ramp its output up and down rapidly. Nuclear does not do that. I believe it is even worse in that way than coal, but I may be mistaken on that.
Gas turbines are among the fastest reacting, but they often cost more per Kwh, and still are not instantaneous. So you have to have both base load capability and peaker capability.

As RE goes, large Hydro is very stable over the day and can be ramped up and down fairly quickly, but the inertia of the water in the penstocks and other feed pipes has to be taken into account.
Micro hydro is vey stable and can be made quickly adjustable (although few can justify doing it) and wind will hopefully average out over a wide area and time of day.

You may be right about how quickly the nukes can alter their output. They would need something similar to a natural gas "peaking" unit to fill in the gap which as you indicate are not necessarily cost effective. Just necessary.

Someone needs to come up with a cost effective way to "ride through" the gap as well as a better "energy storage" system to take them through the night. Maybe in my kids life-time.

[inetdog]

You may be right about how quickly the nukes can alter their output. They would need something similar to a natural gas "peaking" unit to fill in the gap which as you indicate are not necessarily cost effective. Just necessary.

Someone needs to come up with a cost effective way to "ride through" the gap as well as a better "energy storage" system to take them through the night. Maybe in my kids life-time.

Sodium-Sulphur batteries and other current chemistries for gap-filling appear promising on a utility scale, but they take capital expenditure and are still very much in the early adopter stage.

[SunEagle]

Sodium-Sulphur batteries and other current chemistries for gap-filling appear promising on a utility scale, but they take capital expenditure and are still very much in the early adopter stage.

I have seen a few different batteries being tested but have no idea concerning their cost. There is a liquid metal battery design out of MIT being tested that supposedly uses common materials but it must be under a lot of pressure to keep the metal in liquid form. That type of container can't be cheap.

[bonaire]

Iceland does a pretty good job of using geothermal (2/3 of electricity production). But not everywhere is Iceland. I wonder if Indonesia and other ring-of-fire locations could use their volcanos similarly to how Iceland does.

http://en.wikipedia.org/wiki/Renewable_energy_in_Iceland

[inetdog]

I have seen a few different batteries being tested but have no idea concerning their cost. There is a liquid metal battery design out of MIT being tested that supposedly uses common materials but it must be under a lot of pressure to keep the metal in liquid form. That type of container can't be cheap.

Not necessarily under a lot of pressure. At a high temperature!

High pressure alone will not make things like metals fluid.

[SunEagle]

Not necessarily under a lot of pressure. At a high temperature!

High pressure alone will not make things like metals fluid.

I went back and found more info on this battery and you are correct. It is using magnesium solutions and salts heated to 700 C. The design is from a Don Sadoway at MIT. The pictures of the battery "container" looked more like a pressure vessel (cylindrical and flat on top & bottom) than a heated vessel.

[inetdog]

I went back and found more info on this battery and you are correct. It is using magnesium solutions and salts heated to 700 C. The design is from a Don Sadoway at MIT. The pictures of the battery "container" looked more like a pressure vessel (cylindrical and flat on top & bottom) than a heated vessel.

There may be some pressure in there anyway for other reasons. But a cylinder, after a sphere, gives the largest internal volume per sidewall area that needs to be insulated.
A sphere will not work really well in terms of putting the electrical parts inside.

Hot water tanks are traditionally cylindrical more for insulation reasons than for pressure reasons, but both factors apply in that case.
If you need maximum volume per usable floor space in a building, then you have to go rectangular.

[SunEagle]

There may be some pressure in there anyway for other reasons. But a cylinder, after a sphere, gives the largest internal volume per sidewall area that needs to be insulated.
A sphere will not work really well in terms of putting the electrical parts inside.

Hot water tanks are traditionally cylindrical more for insulation reasons than for pressure reasons, but both factors apply in that case.
If you need maximum volume per usable floor space in a building, then you have to go rectangular.

I understand the ease of insulating a cylinder but I also know that a pressure vessel's weak points are at the weld points and flat surfaces which can bulge. That's why a square vessel would have many weak points. Good discussion but it is probably off topic.