This year's entry to the Wolverhampton's Warmest Landing Competition

Finally managed to rig up the Solamiser, to divert excess solar pv generation into space heating. I even managed to run a new circuit, from the garage-mounted consumer unit to the panel heater on the landing, without knocking half the house down and with minimal swearing (first time for everything). So far, we have the Solamiser on a dedicated 16A circuit feeding a solitary 400W panel heater. I have employed a modular 'plug & play' design to make provision for future expansion (which roughly translates as "there's a junction box in the cupboard under the stairs").

Solamiser fitted discretely above the consumer unit in the garage

Well, it works. The moment pv generation exceeds demand, the Solamiser kicks in and the little neon on the panel heater begins to flicker, denoting that the heater is receiving less than it's rated power. As the pv output ramps up, the flicker lessens until the heater is running at full power. The landing is nice and toasty and our electricity meter hasn't moved since I last put the kettle on.

As I write this, at 1pm on a bright, partially cloudy day, the heater is running flat out and we're still exporting between 1 and 2kW. More heaters needed. We're now on the look out for a second hand storage heater or two, to maximise the potential of this free heating system.

The rain in Spain falls mainly down the drain...

...and it did here too, until we finally got round to sorting out a couple of water butts. One of those jobs that we've meant to do for a while. The recent inclement weather has managed to divert a bit off the flat bay roof and into one of our shiny new green plastic tanks, while the other languishes in the garage until we decide where to put it.

The grape vine embraces its new neighbour

 Anyhoo, it's got us thinking about rainwater harvesting and, following on from that, re-using greywater (the stuff that goes down the drain after a bath or shower for example) to flush the toilet. It's as a bit odd that the water we literally flush down the bog is prime drinking quality - what a waste. Especially the amount that seems to, erm, pass through our toilet in a week. At 6 to 8 litres for the average flush, it soon adds up. Using harvested rain or greywater for flushing purposes makes perfect sense. It's a relatively straightforward DIY project, involving some water butts, some pipework, a pump (solar powered of course!), a loft storage tank and some control gear. Greywater, though more plentiful than rainwater (hard to believe at times) does require some sort of treatment and filtration prior to unleashing it on the porcelain, so we'll need to weigh up the pros and cons of each approach.

We've been meaning to get a water meter fitted for ages (we've been meaning to do a lot of things 'for ages'). A meter should dramatically reduce our bill. Flushing the lav from harvested or recycled water should reduce it considerably more.

I knew my allergy to washing the car would prove useful one day...


Incidentally, most local authorities and water companies have special offers on water butts. What you may not know is that pretty much all these offers are handled by one company, Straight plc. - the same people who supply your council wheelie bin. We found that one of Straight's own webshops was offering better prices than our local council or Severn Trent, so it's worth shopping around. We bought from evengreener.com and the stuff arrived within 2 or 3 days.

Talkin' 'bout my generation

As any solar pv system owner knows, more generated electricity is usually exported to the grid than is used around the house. Even on dull days at this time of year, we are generating more than we use during the average day. With affordable storage solutions still a way off and our export payments deemed at 50% of total generation regardless of how much we actually wave bye-bye to, we were left with three options:

1. Do nothing.
2. Get an export meter installed (probably at some cost) and get paid accurately for everything we export, rather than the assumed 50% of total generation.
3. Use as much of the generated electricity (usefully!) as possible, while still getting paid for the assumed export of 50% of total generation.

1. & 2. were quickly discounted on the basis that we were buggered if we were going to give away our lovely, fresh, organic electricity for free, or at some discounted rate, just so that we could buy a load back again in the evening at three times the price. Option 3. it is then: Use as much, usefully, as we can while still receiving export payments for half of it, whether we export or not (I stress the word 'usefully' again - tempting as it is to waste as much as possible just so the energy companies have to pay us for nothing, me no like waste).

The usual way to use up a surplus of electricity is with one of many devices now on the market that dump the excess to an immersion heater, to provide hot water. Such devices monitor export and, by controlling the power to the immersion heater, never use more than the available surplus.

We have a gas-fired combi-boiler, therefore no hot water tank, therefore no immersion heater. I considered using a 15l unvented electric water heater I've got lying around to preheat the cold water feed to the boiler, but Worcester Bosch told me if I did that, I'd break it. However, they did tell me I could spend a fortune on one of their new models, which would accept a pre-heated feed. Er, no ta. Due to the way in which the power diverter devices work, they can only supply a resistive load, ie. a heating element like that found in the average immersion heater. Fortunately, this means they'll also work with electric panel and storage heaters (but only the basic 'no frills' ones without fans, timers or electronic controls). The plan is to therefore divert our excess pv generation into space heating. I've already sourced a snazzy, slimline 400W panel heater which I've installed on the landing and which should hopefully work in conjunction with our 'fresh air' positive input ventilation system, the outlet diffuser of which is located in the ceiling above the heater. I'm hoping for a mixture of pre-heating and destratification, as the two work together to waft gently warmed air around the house. Seems to sort of do something resembling that, following some initial trials.

Slimline 400W heater for 50 quid. Bargain.

 The main business will be taken care of by a couple of 1kW or so storage heaters located in the downstairs living areas. We're currently on the look-out for a couple of suitably cheap, used units to be added as and when. We hope they will be able to take a bit of demand off the gas central heating system.


That only leaves the power diverter device. I have installed quite a few Immersun units for customers with immersion heaters and this high quality, well thought out bit of kit works very well. However, it is far too sophisticated (and expensive!) for our needs. A bit of seasonal space heating will be nowhere near as cost-effective as year round hot water so a more basic alternative was required if this project was going to be worthwhile (not that we've bothered with such trivialities as working out the financial benefits!). The answer came in the shape of the Solamiser, a trimmed down controller with none of the Immersun's bells & whistles. More Aldi than Waitrose, if you will. Still, at a fraction of the cost of its flashier cousin, I am hoping it will perform as good a task. Hoping to get it fitted in the next week or so.

The Solamiser. I might buy a bell and a whistle to pimp it up a bit.

Wolverhampton calling.

Morning all. Watch this space if you are interested in a not-terribly-scientific approach to lessening your dependence on the utility companies and generally greening up your life (by which we hopefully mean 'spending less money'). All views expressed within these pages are purely our own and do not necessarily constitute fact of recommendation. Copy any ideas at your own risk!!