Earth Notes: On G83-Lite: Solar Nanogeneration For Everyone
First written 2009/03/28.
What's stopping you generating your own electricity at home? No roof for solar PV? Don't own the place? Maybe that shouldn't stop you, and without breaking the laws of physics or the land!
In the UK, the "G83" standard essentially allows any householder to connect microgeneration including solar PV and wind totalling up to a little under 4kW (16A per phase) to the grid, and they can't be refused by the DNO (Distribution Network Operator) that provides the mains electricity supply to the house.
But the connection has to be made by a suitably qualified electrician, and basically has to be permanently wired in, which makes any microgeneration relatively expensive and a nuisance to install, and is not going to work for a tenant in for a year or so. (The US government estimated the "soft" costs such as paperwork to be a substantial fraction of solar install costs as of 2011, for example.)
Money and Space
Not everyone has the money or space for a full set of solar panels or a turbine, and not everyone can make expensive permanent property alterations, such as a student in a rented flat halfway up the block, but they might still have decent sunshine 'going to waste' in a southern window, and they might still want to be 'part of the solution'...
I'd like it to be possible for an individual householder to do their bit for the grid with more-or-less the same ease that they buy a new kettle, ie that they should be able to buy a cheap off-the-shelf mass-produced device that they can plug into an ordinary mains socket at one end and at the other a solar PV generating curtain liner or solar awning or shutters, etc.
These would be cheap and safe and simple to use and would make use of a bit more urban land area to generate renewable energy. They could also take the edge off the householder's electricity bill.
Many of the restrictions in the G83 specification are safety related, to protect the owner, the grid, and anyone working on the grid. A pluggable device would have to be further restricted for safety reasons, such as very quickly stopping generation when unplugged to avoid the chance of delivering a dangerous shock to the user.
It would probably also be useful from a safety point of view, but not in practice limiting in device design, to cap the rating of such as G83-lite plug-in nanogenerator to (say) 100W to minimise problems with bad contacts or long wire runs or old supply meters. 100W is probably the most that could be generated from 1 square metre of consumer grade robust PV material (probably thin film) in optimal sunlight for example.
The G83-lite rules might be that each device is limited to at most 100W, and at most 10 devices can be deployed behind one single-phase meter without permission from the DNO.
(2017 note: as more intermittent generation sources join the grid "lite" devices should effectively come lower in the "merit order" and positively help regulate the grid, eg by coming off-line eagerly (but randomly) when voltage or frequency rise by amounts for which normal grid-tie would stay on-line, and with sophisticated randomised reconnection algorithms.)
It might also be necessary to oblige all suppliers to allow G83-lite devices on all tariffs, allowing simple net metering if need be.
(2017 note: as more intermittents come on-line and FiTs dwindle, and to help keep paperwork minimal (if any) and costs low, it may be better not to pay the end user at all, but simply encourage them to maximise self-consumption, and not ding them for having this nano-generation in place.)
A householder with a south-facing room that needs the curtains drawn in summer can then nip down to their local high street and by a solar shade or curtain to hang in their window and plug in. Voila! Instant renewables.
It would have to be seen if it would be possible to make such devices cheaply enough in terms of money and resources to pay back on both fronts if well deployed, but I think it should be made possible, thus allowing almost anyone to become a generator rather than just a consumer.
(Note that existing devices such as the Mastervolt Soladin 120 probably meet the technical and safety and cost requirements that I suggest above, but would need a G83-Lite regime to become legal to deploy in the UK.)
This suggestion has been raised, amongst others, with:
- DECC's Red-Tape Challenge (2011/12)
- Ofgem (2012/02)
- the Energy Secretary (2012/05: "Sounds a great idea - will pursue!")