Now they are talking! This is a wise use of fossil fuels - as a backup to wind and solar instead of the other way around. Wind and solar should be "baseload" power since they are not particularly easy to turn on and off, up and down (not "dispatchable" in gridspeak). Then, use natural gas to supply the peaks and/or fill in when the wind dies. Or buy these CC plants now for baseload, and then convert to peaking power as more wind and solar comes on line.

I high efficiency, high rate change gas turbine is very useful for places where they want to attach a lot of wind.

However, it increases the capital cost of building the grid (or rebuilding the grid).

Initially, you have a grid and generation for a certain population size. All is well, if rather carbon based.

Then, you are mandated to add a certain amount of wind power (or solar), both of which are intermittent and uncorrelated with each other or demand.

So you cannot close any of the old plant, because there will be days when there is essentially NO wind ( say < 5% of capacity).

With these, you can replace the "old" gas turbines with ones which can follow demand faster, but you still have to keep 100% coverage for when there is no wind.

So you can add quite a bit of wind into your grid, Ireland has 1300 MW of 5000, but you can't shut down any old plant, and you have the option of replacing older fossil generators with these faster ramping ones to reduce the chances of blackouts.

It is good, but it is not VERY good.

You get to reduce the carbon intensity of your electricity, but at huge capital cost.

(and high running cost, as you have to keep two sets of people employed to operate the fossil and renewable power sources.

As innovative as these advances in traditional power plant adaptation are... we need to do better. This evolution provides the argument to do so. As mahonj points out the carbon reduction comes at a huge capital cost. And richard's prediction of $0.20/kWh is unrealistic.

We might consider these load following wind/solar schemes a first phase in the energy independence evolution. But we can lower the huge capital cost by implementing a simultaneous emphasis on distributed energy. As grids are converted to renewables with load following combined cycle plants - we need to begin installation of CHP appliances in the single and multiple family residential sector.

PHASE ONE: grid conversion to NG combined cycle, renewables, licensed nukes and thorium, AND NG-fueled CHP appliances in residences.

Without the CHP component we stay on the slow track married to century old transmission systems. GE(or other manufacturer) needs to hedge these investments with CHP/water heater appliances that will allow shut down old fossil plants.

Deterrence from the distributed path will only speed the introduction of Mills and Rossi-type disruptive technology. This is a plan to expand the entire energy portfolio by steady integration of new systems.

Right on Orbrid. Solar and Wind (and other intermittent power sources) have to supply base loads. Controllable power sources such as Hydro and quick ramping up Gas turbines such as these, have to be used for peak demands and periods with lower wind and solar power production.

Unfortunately, Hydro, Nuclear, Coal fired power plant engineers do not want to become second class-place power producers and continue to make Solar and Wind power integration as difficult as they can. Resistance to change is very deep in those groups.

I've always liked the idea of CHP, but improvements in air source heat pumps mean they aren't always the best option.

10kWh of gas in CHP - would give you 3kWh of electricity + 6kWh of heat (assuming 30% electrical efficiency and 60% heat recovery)

10kWh of gas to 60% efficient CCGT = 6kWh electric, say 5.5kWh after transmission. You would then have 3kWh for electric and 2.5kWh for a heat pump. With a COP of 3 that would give you 7.5kWh of heat

Although you arguably get advantages from CHP in grid loading and reliability so the case is by no means closed.

3Peace - the example you provide indicates 2.5kW
electric for heat pumped to 7.5kW (COP 3) heat dependent on air temperature differential. Thermal efficiency of a heat pump drops significantly as the outside temperature falls.

Our local CHP unit delivers 3kW electric at near zero loss, and 6 kW of heat for home heating and hot water. Likely best CHP applications are in cooler climates.

Added benefit of CHP is less load on grid, a LOT less maintenance on grid transmission systems. A LOT less environmental impact to landscape, wildlife, appearances, cost of easements and right of ways. A LOT less cost stringing and burying cable.

Distributed energy also delivers the lowest security risk of any energy system. If a central power plant is damaged - its grid goes down. Distributed energy provides thousands of sources combined into micro-grids to serve neighborhoods and communities. MUCH more secure. Of course the entire game changes with new fuels and catalysts providing CHP input energy.

Hydro-rich territories like Canada will continue to sell energy to those in need of a reliable, sustainable resource. But the value of that energy will decrease as localized renewables expand. Never-the-less, hydro, solar and wind will all function as territorial sources of income to their operators.

Much better to have a diverse portfolio of sustainable energy sources - than a single source. As for CHP, the Japanese Ene-FARM (SOFC) products are selling well and setting the table for western manufacturers:

http://www.fuelcelltoday.com/online/news/articles/2011-02/New-m-CHP-Product-in-Japan