by Jason Heppenstall
As a young boy in England in the 1970s I could be relied upon at all times to be carrying certain instruments about my person that I deemed necessary for survival should I suddenly find myself in a Famous Five type situation. A folding penknife was an obvious prerequisite for getting the bark off branches, skinning enemies alive and digging out the dirt from under ones fingernails. Another essential was a couple of Texan bars and a Yorkie – for nutrition if the world suddenly ended. And finally (usually concealed in one of the many zipped pockets of my Parka coat) there would be a magnifying glass. This was not just useful for studying pirate maps, or analysing the finer qualities of frogspawn, no – it was also a Death Ray. By focusing the sun’s light on a single spot I found I could ignite pretty much anything that I cared to. I once burned a hole through the back of my friend’s blazer during double maths and filled the classroom with the chocking acidic smell of burnt John Lewis. Another time I set fire to a hayrick (to my shame) and was literally chased by a pitchfork wielding farmer. The sleeping family dog’s tail similarly spontaneously combusted once on a Devon beach. That was about the time I had my magnifying lens permanently confiscated.
Roll forward a quarter of a century and move me two thousand kilometres to the south and I’m at it again. This time, hopefully, I’m putting the sun’s rays to a more benign use. Yes, I’ve gone solar.
Like many people it all had to do with a growing awareness of my so-called carbon footprint. We are all net emitters of carbon in the form of carbon dioxide (CO2) into the atmosphere. Since the Industrial Revolution humankind has been (literally) powering forwards by burning fossil fuels; coal, coke, petroleum, oil and a host of derivatives. By removing fossilised life forms from the ground and burning them for their energy value we are unintentionally putting the carbon that was once safely stored into the earth’s crust, back into the atmosphere. This has led to a build up of so-called greenhouse gases that act to trap the sun’s energy and heat up our atmosphere like a – well – greenhouse. All peer-reviewed scientific papers agree that man made global warming is happening and may indeed be starting to accelerate (source Royal Society).
The consequences of this global warming are far too scary to go into here – and it‘s important not to feel too overwhelmed and paralysed by them. As individuals we can ask ourselves what we can do to alleviate the unfolding situation. As a large proportion (up to 30%) of our CO2 emissions come from the home this seemed an appropriate place to start. Having arrived in Spain, like many people we’d purchased a ramshackle cortijo that needed a lot of modernisation to make it habitable. This was an ideal opportunity to study the building, decide what we wanted from it and adapt it in such a way as to be as environmentally benign as possible.
Having arrived from the cold dark north (five years in Denmark, to be precise) the harsh glare of the Andaluz sun seemed a most obvious source of energy. We learned that the sun is most readily available for two types of energy; to produce electricity using solar photovoltaic (PV) panels, and heat water in a solar conductor tank. It seemed crazy to us to see all those red butane gas bottles arriving by truck (most gas is extracted in Algeria and shipped to Spain) when the sun can heat up water easily and freely. I had no idea how much a solar water heater might cost, but guessed at a couple of hundred euros. I was wrong. Multiply that figure a few times and you have more of an idea. I couldn’t see how, what I assumed to be a very basic convection system could cost so much. Although the cost of purchase will be recouped in the future it seems that the initial startup cost was putting some people off. Malcolm de Sta Croix of Solar Conect hit upon the ingenious solution of setting up a deal with La Caixa bank whereby the installer can borrow the amount needed to fit a solar water heater and repay the loan at almost the equivalent rate that he would have spent purchasing gas bottles. So the system effectively costs next to nothing.
Further research into solar water heating has turned up some interesting DIY projects that cost almost nothing. Old radiators painted black can be installed easily as can ex-boilers placed on the roof and also painted with some light absorbing paint. I’ve also seen a perfectly functional and stylish shower block with nothing but coils of regular black plastic irrigation tubes on the roof. The possibilities are endless with a bit of imagination.
Turning to PV, the options were far more complex. Our cortijo already had a solar system installed, albeit a basic one. A single Soviet era panel sat on the roof generating enough power for a couple of feeble light bulbs. The old man we bought the house off couldn’t see why we should want any more than this. A family of tailless geckos had made their home in the inverter box on the wall and a single truck battery bubbled and hissed away in the corner of what was to be our baby daughter’s nursery. Our house needed to be brought into the 21st century.
I have to admit that I had no understanding of electricity whatsoever. I knew it could electrocute you if you stuck your little finger in a light bulb fitting and I knew it was made of small particles called electrons that whizzed around violently banging into other more docile particles. I bought an American book that explained PV and electricity to me as if I were still in kindergarten. Amps were analogous to packs of huskies pulling sledges and electrical resistance was something to do with sticky snow. It was at my level.
Fully clued up I went off to confidently talk to a solar expert about huskies and sledges and all that. The professional engineer from Germany seemed a little puzzled at first but soon saw I was in need of help. He noted down everything that we might want to run in the house, when we might want to use it (e.g. TV and computers at night, sewing machine and iron in the day) and went off to do some complex calculations. When I next saw him he told me exactly what PV system we needed and where we could get hold of it. It was less painful than I had previously imagined.
Just to be sure I asked another expert and was told something completely different. Another one still came up with a third choice. I tried to do some calculations myself but soon gave up. I began to pull my hair out. I spent several months in this state. A kind of solar paralysis came over me and I didn’t like to talk about it because I knew that whoever I mentioned it to would tell me something contrary to the prevailing latest advice. My own calculations were equally as confusing. Scraps of paper littered the dining room table with things written on them like “9 * lghtblbs * 4.5 hrs (avg) + TV (200w?) + 1hr wshng mchn (gen bckup?) = (assmg 8hrs fll sun frm 4 pnls 110w ech)…etc”. Worryingly, whenever I mentioned sacrifice to my wife she raised a concerned eyebrow (sacrifice of the dish washer and popcorn maker that is, not human sacrifice) and said things like “Remember we’ve got children” or “Perhaps we should get a grid connection as, you know, backup”. I was adamant about the grid connection. Plans were afoot to bring the grid to our patch of hillside – which seemed ridiculous to me seeing as everyone was living perfectly OK without it.
And then I got a phone call from someone who said he could help me. I arranged a meeting down on the coast and two weeks later was the proud owner of a solar system put together by an enthusiast and imported from the four corners of the globe. The panels came from Japan, the batteries (monster ones weighing over a hundred kilos each) from Canada, the inverter (the box that sits on the wall and converts battery energy to useful electricity) from Switzerland and the other bits and bobs from the UK. Four not-so-sunny countries with better developed alternative energy industries than sunny Spain.
The six panels themselves are high powered ones that sit in two arrays of three on our roof and the inverter is a meaty 4,500 watt – enough to power all the mod cons found in a regular ‘grid connected’ house. For backup we have a petrol powered 8kva generator for times when perhaps several consecutive cloudy days have depleted the batteries or we’re running every single appliance we own continuously. In these instances the backup generator switches on automatically when the inverter detects a low level of battery power without even a blip in the supply. the supply itself is pure sine wave, which means there will be no annoying hum on audio and video equipment, as can happen with non sine wave inverters.
The total cost of our ‘overkill’ system was around €12,000. This came out as average when compared with other estimates we had been given, which ranged from €4,000 (a complete DIY job) to €22,000 (a rip off). Given that we would have had to pay €8,000 for a connection to the grid this means that we have spent an extra €4,000 – with the added bonuses that from now on all electricity will be free and we know that our electricity needs are generating very low levels of CO2 (although not zero when one takes into consideration the production of the materials and the long distance shipping).
Next on the list of considerations was internal heating. No heating existed apart from a large open fireplace and a blackened hearth in the kitchen. But before considering what type of heating to install we learned that the best way to think about things was to start by asking ourselves what kind of temperature we ideally want. This might sound like a simple question but it may well be the cause of numerous marriage break-ups (someone should do a study on this). My wife, despite being Scandinavian, likes to bask in heat. To her anything below 26 degrees is ‘chilly’. I, on the other hand, was raised in a house with a father who cursed the very concept of central heating and thought anything above about 14 degrees was ‘boiling hot’. In winter we had to wear gloves indoors. I am therefore naturally attenuated to cooler conditions (perhaps it’s genetic?) and can wear a tee shirt in conditions that make my wife turn blue. So, after some horse trading, we have agreed that a temperature of between 18 and 20 degrees is ‘reasonable’ in winter.
How to achieve this target temperature? The first thing to consider is insulation. There are many types on the market, some being highly artificial, such as polystyrene, and some being more organic, such as wool and straw. The most important factor to consider with insulation is the u value. This is simply the measure of the conductive properties of the material – a lower u value means less heat can escape (or get in during summer). Use can again be made of the sun by installing a large south-facing window and building an interior stone wall behind it and painting it with very dark paint. This is an ingenious method for catching winter sun because the winter sun, being so low in the sky, only falls on your wall during this season i.e. when it’s most needed. The solar rays are absorbed by the heavy stone in the day and the heat radiates out slowly throughout the night, heating your house in the process (see diagram). During summer the sun is too high to hit your interior wall and you are spared being roasted inside your own home.
As far as burning fuel is concerned for heating, one of the most carbon benign ways is to install a pellet burning stove. These are just catching on in popularity due to their incredible heating ability and efficiency. They burn small wood pellets manufactured from ‘waste’ wood from sawmills, which are fed into a hopper inside the stove. Compared with burning regular wood these stoves are far more efficient. Up to half of the energy in a log goes up the chimney and is wasted when burned, compared with only 20% in a pellet stove. They can even be connected to hot water systems and will heat an entire house for, it is said, less than €1 a day in winter. And because they burn wood they are said to be ‘carbon neutral’ in as much as the carbon released into the atmosphere by burning the wood is removed again during the growth of a replacement tree.
For ourselves, however, we have opted for a regular wood burning stove, primarily because much of the fuel will be sourced from our own land. The key thing here is that wood should be burned at a high intensity to get as much heat from it as possible – a smouldering log is a wasted log. And besides, there’s nothing quite like sitting by a roaring log fire on a cold winter night, glass of vino dulce in one hand and a copy of George Monbiot’s “Heat; how to stop the planet burning” in the other.
And our next project? Construction of a solar oven from a bundle of mirrors I found on a dump in Copenhagen. I need it to be powerful enough to bake bread. Anyone got any tips?
For a reliable solar advisor and fitter in the Granada province contact Gary Builds on 618 484 313
Editorial Comment
When it comes to energy Spain is in both an enviable and an unenviable position. Those of us who may hail from Britain or the Netherlands or anywhere else in northern Europe have little idea how it feels to be so reliant on imported energy. It may come as a surprise to learn that Spain imports over 99% of is oil and gas – mostly from north Africa and the Middle East. And with a booming economy reliant on cheap and plentiful fossil fuels, Spain can ill afford to rock the boat and risk upsetting any of its import markets.
Yet at the same time Spain is in an enviable position when it comes to a future home grown market in renewable energy. Most of us, to a greater or lesser extent, associate Spain with the sun; it shines more in this corner of Europe than any other. What’s more, Spain’s politicians recognise this and are keen to exploit this free and clean form of energy. No ideological constraints bind Spain to fossil fuel in the way that they do in, say, the USA. That’s why in 2005 the government approved the Renewable Energy Plan (Plan de Energias Renovables) which aims for a 30.3% target for electricity production via renewable means by 2010. The means by which politicians hope to achieve this target are through an aggressive programme of building new energy infrastructure – relying mostly on biomass, solar photovoltaics and wind, as well as small scale hydro electric projects. Twenty three billion euros have been earmarked for the project and it is hoped that, aside from the environmental benefits, Spain will become less reliant on importing energy from potentially unstable foreign suppliers.
Can this be achieved? On current eye witness evidence it seems certain that something big is happening. Driving through the plains north of Madrid one travels through a plane filled with thousands of windmills. And who could have failed to notice them suddenly lining the hills above Motril? Don Quixote would have been maddened by all these ’giants and monsters’ – as are the remaining sceptics who deny that climate change is a major threat.
But we should not be too quick to congratulate the government. As was reported in the very first issue of The Olive Press Spain’s CO2 emissions have sky rocketed – rising by 53% in the past 15 years alone. The country’s Kyoto responsibilities seem to have fallen by the wayside somewhere along the line.
And we should also scrutinise the figures to see exactly what the government constitutes as renewable energy. Some methods of obtaining ‘environmentally friendly’ energy are more controversial than others. Hydro power accounts for the majority of megawatts generated by non fossil or nuclear means and yet who would argue that vast new dam projects are the wisest use of nature’s resources? Similarly the production of some so-called biofuels such as sugar cane and straw can lead to a loss of biodiversity. Who would want to live in a world where the big energy companies own most of the productive land – even if the product they produced was ‘carbon neutral’?
The concept of energy conservation is noticeably absent from the government’s new energy policy as well. Vast amounts of electricity are wasted through unnecessary lighting (including street lighting), appliances left on or in standby mode and ‘leaked’ from the national transmission system because the point of production is often far away from the point of use. And it is not clear whether the renewable energy target refers to electricity pumped into the grid only or whether it includes small scale non grid connected production such as locally sited solar panels. Small scale ‘home’ production is by far the most efficient in terms of transmission loss. When the Renewable Energy Plan was announced it was initially reported that every new building in the country would only be granted a license if it was fitted with solar panels. Not much mention has been made of this since and it remains to be seen whether this was merely political rhetoric or reality.
Nevertheless, despite the shortcomings, one must hope that a seismic shift is taking place in terms of how Spain and the rest of the world views energy. In the past it was all about security of supply – which really meant which country should be invaded and controlled. After all, who was it who pointed out that Burma, one of the world’s most repressive regimes, could sit tight safe in the knowledge that not a drop of oil existed under its surface? And the future will, of course, be about energy security too. But perhaps – just maybe – politicians and citizens are starting to realise that, like charity, energy security begins at home.