Re: Can't they upgrade it?
The generator at Smithfield is the old Port of London Authority site, now privately owned and operated primarily for a medium sized heat network, and the electricity is exported to the local grid. It is profitable for the company concerned, but only because they didn't incur the costs of constructing the heat network.
As far as I'm aware, the Greenwich power station plan is still on hold. Realistically it isn't large enough to be cost effective, and with falling wholesale prices and concerns about London air quality I'd be surprised if they can make a good case for it. Then again GLA are a bunch of muppets who actually want to run their own power company, this may be forced through to meet that desire, after all, its only other people's money they will be spending.