Build This Idea: Micro-Grids for Peer-to-Peer Energy

This is an instalment of Build This Idea, where I write about stuff I want to exist. Treat it like an idea store; if you like something, take it; if you make it, let me know — I’ll be delighted to check it out. Today, a rather big ask for unifying several existing concepts and services.

London has canals. On canals there are moored houseboats. Until recently many houseboats had a diesel generator for their own electricity. Now it is common to see a photovoltaic panel or three supplementing that, and I’ve seen a few wind mini-turbines (though I’m a bit skeptical if they produced more than needed to light a lightbulb).

A thing that is not so great about this is that each boat has their generator, and they aren’t connected. There are many downsides to grids, but if you’re running a heavy load (kettle, oven) and your neighbour isn’t, a grid is a handy thing to have. A grid lets you pool resources, essentially timeshare.

But we don’t always need country-wide grids. Much of the averaging and pooling is feasible on neighbourhood or city scale. Traditional large-scale grids are most useful with centralized generation, and actually have problems with independently operated small-scale generation.

Instead, we should connect the houseboats with micro-grids. This should also be done in other cases where people use electricity in geographically close but off-grid situations, such as parked RVs, camped tents, or clusters of cabins. This would help with temporary heavy loads: your panel or battery might not be able to support a kettle or a vacuum on their own, but together with those of two of your neighbours it might. Then once your kettle is off, your panel can lend electricity to your neighbour. Try to smooth the peaks a little. Keep a running balance of how much electricity was lent and borrowed by everyone to ensure fairness.

To further motivate peak smoothing, have a surge multiplier that rewards providing energy to the grid at peak times by giving out extra credit. During a lower-demand period, the credit can be spent by receiving more energy than lent out at peak. (This is essentially demand management by economic means.)

A rough implementation idea: each houseboat or tent or RV is a system, identified by a unique key (possibly something similar to public/private key). New systems joining a grid (with a new key not previously seen by the grid) are required to lend some energy before being allowed to borrow. This privileges early movers and existing micro-grid members, but also avoids regenerating keys to repeatedly get free energy. Wireless power transfer guided by low-power beacons would make it super cool, but of course there would still be a lot of value in wired connections. Systems can connect and disconnect as they like or need, but will find it advantageous to keep connected as much as possible, to build up credit they can spend later.

Another reason this would be interesting is it sets up a new “edition” of an electrical grid where there was no grid before. If all you had before was your diesel generator, you are more likely to accept limitations on electricity use than if you’re coming from a grid-connected point of view, where this setup might be a downgrade. Further, a secondary grid where the expectations are different can be a good illustration of the concepts of demand management and peak smoothing for people who are used to current constant grids. In software terms, this is a new, rewritten “edition” that doesn’t have some features, as opposed to a new “version” removing features.

The new edition should optimally be built to be a little more resilient and better able to deal with fluctuating supply and demand. Current systems are built assuming 100% reliability, and weird things happen if grid power goes out or voltage drops. However, many of modern household uses of electricity are not particularly time-critical: increasing amounts of electronics have built-in batteries, and in many cases it doesn’t really matter if a fridge or heater turns on five minutes earlier or later. It would then be good to have smaller-scale dispersed generation as well as storage, with house, vehicle, and electronics batteries all capable of being charged or discharged as needed.

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