http://www.nationalgrid.com/uk/Gas/soincentives/consultation/ which it invited me to look at (half way down page 43) and respond to. The section concerned seems to be about NG making money available for development, which is not important to me at this stage. I'm trying to see if there would be a positive and valuable role for microgeneration to play soon in grid stability, with a possible new revenue stream over and above pure energy sales and/or ROCs.)
I'd argue that NG is looking at the distribution problem from the wrong angle. Virtually every current office network is based on the 'Ethernet' design with no central control and many, many participants. WiFi LANs and mobile phones do have a stronger central coordinating system, but would again be non-functional without significant distributed intelligence/control. Although I can see that it is much easier for the NG to control large lumps of generation on demand, if we move towards something like that envisaged in the [archive] Home Truths report where there is in effect no baseload, and households are net power exporters, then the NG and its successors are going to end up dealing with something like my suggestion anyway, I believe.
I fully accept that some cases cannot be completely covered by, for example, the distributed system outlined above triggered by line frequency alone. Since the UK grid is synchronous then its frequency is uniform everywhere. But there may be transmission constraints due to outages or upgrades, etc. So a lack of power in Land's End is not helped by injection of more energy at John O'Groats and vice versa. While the distributed system remains small this effect is not catastrophic. But it needs to be dealt with by improved 'intelligence' if and when its contribution grows relative to centrally-dispatched balancing support.
(Note that a grid-tie inverter's response to deviations from nominal/centre frequency can be deliberately made asymmetric. The inverter can continue to power the grid for a much bigger drop from nominal than rise from nominal (frequency primarily, but maybe voltage too). Then the inverter/microgenerator is effectively providing a type of 'reverse dynamic demand' support to the grid.)
National Grid ESO is replacing some frequency response services with new schemes:
Dynamic Containment (DC), Dynamic Moderation (DM) and Dynamic Regulation (DR) make up our new suite of Dynamic Response Services. Together they work to control system frequency and keep it within our licence obligations of 50Hz plus or minus 1%. DM provides fast acting pre-fault delivery for particularly volatile periods, and DR is our staple slower pre-fault service. DC is our post-fault service.Meanwhile, 16WW chips in with free crude frequency response to help admit more renewables to the grid!