
Wednesday, October 22, 2008
Shooting the breeze

Monday, September 15, 2008
Wind turbine: the start
Beginnings: We've started the lengthy business of investigating the possibility of installing a wind turbine. I'd already homed in on Proven as being the best of the bunch of small wind turbines. The 6kW machine looks like the one we'd opt for, the aim being to provide much of our power and to export the surplus to the grid. The video is of one of the four 6kW Proven turbines which form the backbone of the island of Eigg's grid during a visit in June. Most of the noise is the rumble of the strong wind in the camera's microphone.
Site visit:
Anemometers away! You can purchase an anemometer kit for just over £100. Tony Carver
And the economics? Will the outlay be justified? We're looking at a capital cost in excess of £20,ooo. To put it in other terms, that's a lot less than a luxury SUV which is guaranteed to guzzle energy and money. In contrast, this machine -- with a design life of 25 years -- will generate money every time the wind blows above its cut-in speed of around 2.5m/sec. Unlike some turbines, this one doesn't shut down in severe gales. It just carries on generating at its maximum output of 6kW.
When I started thinking about turbines, I did so from the point of view of being green. I no longer see it like that. I'm now interested primarily because the machine can reliably generate money. Which is better? I wondered. Have the money in the bank with inflation going up, stock markets going down and recession looming? Or have the capital asset of a sturdy turbine which could be generating me a thousand or two each year? Add on the rapidly increasing costs of electricity supply, the increasing ROCs (explained here) and the near certainty that even the laggardly 'green' British government will soon have to instigate a feed-in tariff scheme, the cash generation potential of my turbine can only increase. That's what I'd call a good and secure investment... green too!
But it could all come tumbling down at the next two hurdles: wind speed average and planning consent. You'll be hearing from me again...
Thursday, September 27, 2007
Warm at last!
Wonderful to be warm! The most obvious immediate benefit is that the core of the house, previously like a cold store even in summer, is now permanently warm. The temperature outside last night dropped to 3 degrees Celsius but we were perfectly warm in our living room, needing no additional heating. Remarkably, even late in the evening, the conservatory still felt quite warm. So we really are reaping our passive solar gains.
Battle against the weather: This summer has been lousy. A lot of it was dry but cold, but there have been long periods of 'unsettled' weather; Met Office parlance for rain and wind. Whilst there was no glazing, the concreted floor (see photos) repeatedly flooded and had to be pumped out. I developed a sort of 'cut and run' strategy for working, keeping all my tools in a wheelbarrow and coming out when the rain stopped. I'd work until the next rain and then trundle everything away into shelter. This is no way to work but I had no choice. Latterly, we did have a few weeks of dry weather which was perfectly timed for me to get on with glazing the roof and then the windows. Glazing the roof was what one might term 'a non-trivial operation'. (It said in the assembly instructions something like, "Now glaze the roof"!) Doing the lead flashings before that was also quite difficult, lead being heavy and difficult to fit in the continuous slot I'd cut in the wall of the house. But the roof glazing took the biscuit for difficulty: the glass units are heavy and locating them tricky. The seals for waterproofing are fiddly and messy (silicone all over the place). But I managed in about 2 weeks of struggling.
Last minute: The last pieces of glazing went in the east gable end a matter of 2 hours before the rain started again, just in time to stop the loss of warm air from inside the structure. From that time on, it's been a different world inside. Lots of light, warm space and the wonderful feeling of warmth flowing into the old, formerly cold, stone building -- all for free and without burning any fuel. There are a few small leaks which I have to sort out when the rain stops but otherwise, it's really great. Everyone should do this if they can. It really makes a difference!
The next stage: To gain the full advantage of this structure, I have to complete various things. One is the floor which I shall insulate. Another is the internal wall plastering and painting with a tinted paint ('sandstone' is the name of the tint). White houses are a serious mistake; very pretty but cold. It's just like the (vanishing) Arctic sea ice. Being white, both reflect almost all heat away. A dark wall or ice-free sea surface absorb most of the solar radiation and so heat up: good for warm housing; bad for warming oceans and accelerating ice melt. It's the albedo effect and it applies to houses just as it does to the Arctic Ocean. Ideally, I'd paint the internal wall black to absorb as much heat as possible and act as a massive heat store. But one has to compromise. A black house is not acceptable! So it's going to be that sandstone tint. Even so mild a colour makes a difference too. On a sunny day, place your hand on the white paint and it's cold. Place it on the sandstone paint and it's nice and warm.
Controlling the warmth: I also need to investigate simple control systems to duct heat actively into the house, using a fan, but only whilst there is heat to duct. In other words, I need to devise a simple system which switches on whilst it's hot in the conservatory and off when it's not. It would ideally recirculate the cooler air from the house into the conservatory for re-heating. What I don't want to do is dump heat into the atmosphere if it's needed in the house. If you, reader, have any ideas about how best to do this, please leave a comment below this post. I'm sure there are systems available so I don't have to re-invent the wheel.
Details of the building: For those interested, the U-value of the low-e double glazed units is 1.3 (Planitherm). The conservatory was manufactured by Portland Direct, the DIY branch of Amdega, all made from treated and painted softwood from (they claim) sustainably managed Scandinavian forests. This large structure cost around £10,000 delivered, with telephone back-up support available and very good. It's guaranteed for 15 years. The other bits and pieces (like blocks, cement, lead and so on) have probably cost another £1500 or so.
Then there's the small matter of my labour. I started excavations in January and completed the glazing in mid-September. I have probably spent one third of my available time working on this during that period, saving 4 weeks away in Scotland. Val has helped when needed, particularly with laying concrete and holding things in position and I have employed Simon, a carpenter friend and one of our organic veg customers, for 4 days in total. That's about it. Hard work, definitely a 'non-trivial operation' but rewarding. Most reasonably fit (I'm aged 60) and reasonably competent people could do similar. Building is, in part, a question of thinking things through slowly and carefully before doing them and using ingenuity where possible to save time and trouble. So... go for it!
Tuesday, April 24, 2007
Going down; going up!

Going down: At last, the digging out and barrowing on tons of boulders, stones and earth are over. The deepest part of all was the foundation for the 'dwarf' wall which will support the conservatory structure. Here (right), Val is checking the base level of the foundation trench with the water level (see previous post). Fortunately, because the ground is so hard and stony - thanks to glaciers 14,000 years ago - foundations can be minimal.

Sub-floor complete! I finished pouring the final load of concrete just the day before it started to rain, the first rain for about 5 weeks. I'd worked 5 days previously, about 3-4 hours each day, making concrete, barrowing it and pouring it into 'cells' formed by pieces of timber. The top of each timber Val and I had carefully levelled (water level again) to ensure that the top of the levelled and tamped concrete would be about 100mm below the finished floor level. This leaves room for the underfloor insulation. As I write now, the concrete slab is flooded with water from all the lovely rain.
The next step: The conservatory frame arrives on a lorry in 3 days, complete with all the double glazed low-e glass ready to be installed when the frame is up. When the rain stops, I'll get on with building the rest of the dwarf wall at which point the excitement starts: will the frame fit? are my measurements correct? how long will it take? Already, the pressure's on... we've got our table and chairs on the new concrete floor (photo 3 behind) and look forward to having the finished structure which, we hope, will solve many of our old house's heating and insulation problems. We are, in short, fed up of living in a permanently frigid house. (It's frigid because there's no proper insulation and we refuse to run oil-fired heating except for an hour or so in the early morning.) The conservatory will help immensely because I intend to arrange for surplus heat to be ducted into the old house, effectively using the walls as a heat store. How effective this will be we can't be sure but it certainly will be better than the way things are now!
Wednesday, January 24, 2007
The Grand Conservatory Project: space heating from the sun
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Construction - mostly destruction at this stage - is underway. I've been nipping out for a few hours most days when the gales and heavy rain stop to remove a rockery and completely rebuild a clawdd wall. This is to make space for The Conservatory which, we hope, will result in a much warmer house, partly because of its insulating properties on the solid stone wall of the exposed front of the house and partly because I intend to duct heat captured inside the conservatory into the usually-cold inside of this traditional farmhouse. I hope the walls will act as a heat store. That's the idea anyway. Any ideas for simple control devices and fans welcome! (Please add a Comment.)
Now that the rockery and wall are 'rearranged', there's a lot of heavy work ahead shifting barrowloads of soil and rocks. I've tried to arrange things so that I don't have to move stuff twice. So the biggest boulders - some of which I could only just manage to slide or roll - will form the basis of a new rockery in the middle of the garden, burying the existing ugly concrete path which with dozens of barrowloads of soil. So most of the excavated materials aren't 'waste'; they're useful in a new and more attractive context: a rockery in the middle of a single lawn no longer bisected by the ugly path to the gate which was never used anyway.
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Now that I have the detailed drawings of this conservatory from its manufacturer, Val and I set up a datum level which is based on the distance between the base of the upstairs windowsill and the top of the conservatory 'wall plate': the highest timber of the frame which is bolted to the building. I have to leave space below the sill for flashing to go in or it will leak. That done, we checked with a water level that both sills were the same height (they weren't) and measured down to a point which is 1 metre above the finished floor level, marking this with a line. I then attached one end of water level to the wall. This means I can attach the other end of the level to a measuring post whose length below the level is at precisely the depth below the finished floor level that I need to excavate. That is 1.2 metres for the path which I will make along the front of the new structure, allowing for a dampproof course to be made at floor level in the dwarf wall which I will build to support the conservatory frame and glass. The glazing, by the way, will be low-e glass, double glazed, with a U value of about 1.3. Pretty good.
Excavating is the way it's going to be for a few more days if the long-awaited colder, drier weather persists. Then the fun starts! I have to break up the existing concrete 'patio' where the conservatory structure is to be built. This is a hodge-podge of patches of different concrete and different levels and so, unfortunately, has to go. Will I do the breaking by hand (sledge hammer) or hire a hydraulic breaker? I think the latter! But do watch this space...
Thursday, December 21, 2006
Good news and bad news

First the good news: we got planning permission for the large conservatory that we wanted to build onto the front of the house. The intention was and is for passive solar heat capture. So now I'm starting the major excavations needed to prepare for the foundations and insulated floor. We're aiming for low U values throughout the structure so the floor and support wall will be well insulated. I try to do a couple of hours of levering and excavating of huge stones each day.
Now the bad news: Despite trying hard to get everything right so far as building regulations are concerned when constructing the eco-cottage, we've failed on several things in the final check. We are both quite angry and upset about this because we feel strongly that we just didn't get the support we needed, as self-builders, during construction. Let's hope matters are resolved satisfactorily when we meet up with the Building Control Manager in early January. Elsewhere in Europe, self build is common but in the UK, very few people have the courage and commitment to do it themselves. Part of the reason, I'm sure, is because 'the authorities' don't much like them and the system simply doesn't allow for non-professionals to receive kindly guidance so that they get the regulations bit right first time. In our case, you'd think that our cottage would be a shining beacon of effective renovation and proper construction for the low carbon build which we should all be aiming for. But nobody seems interested in our massive insulation and SAP rating of 107 (the maximum possible is 120). Shame!
Saturday, November 11, 2006
Getting real... about pumps

It's taken some time for the light to dawn: pumping water with 12 volt batteries is an expensive waste-of-time. I've been through several pumps and lugged several generations of heavy lead-acid batteries across the field and finally accepted the blindingly obvious: a mains powered pump is a much easier and more reliable solution to keeping the rainwater tanks (for polytunnel drip irrigation) full. Originally I'd intended to power the whole system by wind or photovoltaics but the expense and complications of doing this meant that I never did it.
So I bit the bullet last week and unrolled a long coil of cable - the run is about 80 metres - and now have an almost-silent submersible pump which pumps the rainwater collection ponds in about one tenth the time of the 12 volt pump (which was twice the price), its predecessor. It also automatically switches itself off with a floating switch. Now I can relax in front of my widescreen telly...
Moral: Avoiding using grid electricity for 'green' reasons can often be a much bigger waste of resources, not to mention a very big waste of money.
Thursday, September 21, 2006
Eco-farm project: conservatory and planning permission
Val has now got design plans from a conservatory manufacturere (Baltic wood from 'managed' forests, whatever that means) and in the next couple of days, we'll complete the application forms and submit them. Then there's a wait of 4-6 weeks before we get the answer.
We may, however, design and build the structure ourselves as we did for the holiday cottage conservatory. It all depends on the specs we want being satisfied and the overall strength of the structure: it has to be able to withstand the fierce gales we get here at this time of year.
Sunday, September 17, 2006
Mur Crusto eco-farm project, Llangybi
- To be energy autonomous: an example of low-energy living with carbon emissions cut to a small fraction of ‘normal,’ based on retrofits to existing buildings (difficult but no alternative) rather than new build (easy).
- To be sustainable: growing quality food without high energy inputs and without pollution
Development so far
- Successful organic veg- and fruit-growing box scheme provides wholesome fresh food to local people (around 35 families), with zero ‘food miles’
- Barn conversion to holiday eco-cottage completed in 2006 by ourselves and now successfully attracting regular visitors. Exceptional attention to insulation (see image, sheeps’ wool) and use of renewable electric power (from Ecotricity) means that this building has a SAP rating of 107 (max. possible is 120) and zero carbon footprint. Heating is electric underfloor and is only needed in the coldest weather. Top-up heating is by efficient log-burner supplied with wood from farm: carbon neutral. Double-glazed conservatory provides major solar gains for whole building.
- Minimsed carbon emissions from Mur Crusto house by universal use of low energy bulbs, pipe lagging, insulation where possible and minimal use of central heating after installing new efficient boiler
Planned development
Problem
It is effectively impossible to insulate existing farmhouse because of its thick stone wall construction. It cannot be insulated on the inside because the rooms are already small and dark. Internal dry-lining would worsen this and require total interior demolition. , To be effective, external insulation cladding would require raising the entire roof and re-slating. Insulation in roof spaces already 300mm rock wool but much of the roof is inaccessible because of dormer window construction. Result: building is still a major source of carbon emissions from central heating oil with SAP probably below 30. It is also permanently cold. At present, we produce a minimum of 2.5 tonnes of CO2 per year with the oil-fired heating, run as little as possible. Main heat source is wood-burner (carbon-neutral) and well-insulated bodies. i.e. we wrap up well and try not to shiver when other people would just switch on the heating!
Solutions - in order of priority and dependant on our resources
1. Installation of double-glazed (e-glass) solar passive/semi-active heat collector/conservatory along south-facing front of house to cut down heat loss through walls and induct solar gains with controlled fans into house interior (using thermal mass of thick walls to store heat)
2. Installation of one or more Windsave 1kW turbines, grid-connected. Electricity savings such that one turbine should pay for itself in 5 years
3. micro CHP (combined heat and power, image right) installation instead of existing oil boiler. Savings of 1.5 tonnes/y of CO2 emissions normal for such installation
4. photovoltaic array, grid-connected, on south-facing and sloping roof of modern barn (consultants: Dulas Ltd, Machynlleth)
Final result
An energy-neutral sustainable farm, probably the first of its kind in Wales. Watch this space...
Thursday, July 20, 2006
Feeling the heat in 'rainy' Wales

This picture shows one of the rain water collection ponds outside the polytunnel. At present, they're pumped dry since there's been no rain.
Outside, I have to water the veg plots every night, each sector in succession. There hasn't been any serious rain for many weeks and the Met Office is not projecting any in the coming weeks, so far as I can see.
So we're having the hottest and driest summer since (my) records began... 6 years ago. That may mean nothing in climate change terms but it does make you think. And it reminds me once again how much easier it is to grow veg here than it was in Mallorca, where I used to attempt to farm on a small scale for several years. There, we had to rely for all our water on an old well which in times past supplied plenty of water, but all our rich neighbours had put down tubewells to far greater depths than our well's modest 8 metres and depleted the local water table to keep their vast lawns green and swimming pools full. Here in Wales, we have metered mains water which is unlikely to run dry... and, after Mallorca, I always appreciate the rain when it does come!
Thursday, March 09, 2006
War on the atmosphere: military aircraft emissions

Aircraft emissions and the atmosphere: Okay, here's the issue: we know aircraft emissions are really bad for the environment, especially those at high altitude. Just how much fuel do the airforces of the world squander on training flights (or war games for big boys and their very expensive toys as I'm uncharitably inclined to regard them after the tenth jet in twenty minutes)? What proportion of total aircraft emissions do they represent? I have no idea but I'll bet it's more than you might think. No doubt it's a closely-guarded military secret. And what's it all for? That gross euphemism 'defence' (Orwell warned of this) is bandied about by politicians everywhere. But what's the point of it all (and upgrading nuclear 'deterrents' come to that)? In what way are these scary warplanes and their undoubtedly skilled pilots increasing our security in Britain? Consider little Costa Rica appropriately about the size of Wales: This little country doesn't have an airforce or any military force. The country is still there... and it has land borders with its neighbours making invasion easy, unlike seabound Britain.
Is war more important than climate? The biggest problem facing the planet now is climate change. Most of us, including politicians, would agree with that. So who is about to attack the UK which requires a large active fuel-burning airforce to repel? Terrorists? But everyone knows that terrorists' weapons are suicide bombers and cars packed with explosives. They don't use aircraft - except as flying bombs, one infamous day, in 2001. So why must we put up with this squandering of limited resources on things like military aircraft and the resultant pollution which endangers everyone, not to mention useless nuclear weaponry? Or is there another agenda we ordinary folk don't hear about, like invading Iran - as if the disaster of the US/UK invasion of Iraq wasn't lesson enough? Or maye it's just successive UK governments' desire to have access to the 'top tables' with their American friends, perpetuating the absurd post-colonial notion of 'punching above our weight' and the so-called 'special relationship' which must be nurtured at all costs? That's a lot of questions but how can I get some answers? I have asked my MP to enquire and he is doing so.
Lives are at stake here.
Monday, February 20, 2006
Every little helps: alternative energy sources

The problem with alternative energy sources is that they're either periodic (like tides or solar) or unreliable (like wind). The one exception is hydropower.
But isn't this the biggest obstacle to the wholesale adoption of renewables in the near future?
Well that was how I thought until my brother-in-law pointed out that every unit of renewable enery produced is a unit of fossil-fuelled energy saved. Blindingly obvious, of course, but I hadn't quite got into thinking that way. I had been commenting that all renewable generators required a battery or back-up system which was expensive and likely to depend on fossil fuels - or nuclear power. None of this alters the basic premise that a unit of energy produced (by, e.g., the turbine on your roof) is a unit which doesn't need fossil fuel to make. I repeat myself, I know, but then this is so fundamental, it needs to be repeated. And the argument about back-up sources really isn't very critical since the fossil-fuelled kit (power stations) already exists. Better weather forecasts mean that extra capacity needs can be anticipated well in advance so that boilers and turbines - not something you can swtich on and off at will - can be started. The aim, after all, is not to cease burning all fossil fuels, but to reduce their use by 60-80% to help stabilise the climate.
What's more, the larger the transmission grid (I know there are losses here), the more it can be used as a 'battery'. Gales in Scotland mean surplus generation for that part of the country which can be 'exported', via the grid, to areas of calm. Indeed, such grids cross national boundaries (like the connection between France and the UK) which enlarges the scope of renewables even further. Perhaps it would be feasible for large scale solar electricity to be produced in hot deserts like the Sahara, at the same time giving those countries a new exportable commodity.
Like I say, every little helps...
Tuesday, January 17, 2006
Advice to a daughter (with kids) in a warming world
"As the temperature starts to rise abnormally because of human activity, feedback mechanisms will turn harmful in their effect, and put the situation beyond our control." James Lovelock, Independent, 16 January 2006.
(http://news.independent.co.uk/environment/article338879.ece)

Lovelock's gloomy prediction is depresssing, of course, but I was of the generation which grew up with the serious threat of nuclear armageddon. And we all just carried on doing the things ordinary people do, hoping that matters would improve. They did. I think Lovelock's is very much the worst case scenario and he may be wrong about irreversibility having been reached already. We have to assume that we still have time and do our damndest to kick the politicians into some serious action. Obviously, actions begin at home, but we need much more than this. It's all very well me turning the heating off and refusing to fly but it influences hardly anyone. What is needed is carbon rationing right now, internationally. How can we make the politicians do it?
(For details of how carbon rationing might work, try this guide:
http://tiki.oneworld.net/global_warming/DTQ.html)
It's not just apathy: We had a friend and his wife for a meal recently. Nice pair, normal people, quite aware... and they're about to fly off to Australia for a holiday for 5 weeks. Then he's off skiing. He knows the basic issues but somehow, like almost everyone, he must feel that what he does makes no difference and doesn't really believe warming is happening so he might as well enjoy life. How can we tackle this understandable view?
Linked in to all this is the staggering increase in global population. When I was born (1946), there were about 2350 million people. It's now almost 6.5 billion.
As for Amy and Thomas' future, I think low-key thoughtful preparation for a more difficult world would be a sensible option. You're better placed than many to become moderately able to grow your own food and fuel. Could you also influence their school to teach more in the way of self reliance and alternatives to oil-based lifestyles? Please don't despair: there's plenty to live for and we all have to die of something!
Thursday, January 12, 2006
Sad remains
Wednesday, January 11, 2006
Trapped: it's the planet, stupid!
Even now, many countries behave as if they were not all connected to and dependent on the biosphere, a lesson still not understood − particularly by nationalists. The universal excuse for doing nothing is always ‘the economy’.
So what’s being done? Not much. What are the stumbling blocks: one, ironically, is democracy because it ensures that nothing unpopular can be done; worse is outright denial that there’s a problem at all. Yet there is a way forward, difficult but possible. Otherwise we’re back to the dilemma we all face: the planet’s cry for help isn’t getting through. It seems we really are trapped.