When we bought the house it was not connected to mains electricity. Our predecessors managed with a small diesel-run generator but this was noisy, smelly and dirty: the complete opposite to how we had imagined living in our dream valley. So we were faced with a choice: connect to the mains electricity 2 miles away, or explore solar. The latter was attractive for all sorts of reasons: environmentally-friendly, self-sufficient, avoiding the famous blackouts of Spanish electricity, government grant, less upheaval, no trenches to be dug or pylons erected. I’m not entirely sure we knew what we were taking on when we decided to go with solar. Five years later, with what we know now, would we have chosen mains electric? No. But we would have installed solar differently. Hindsight is a wonderful thing and our installation went in at a time when country houses such as ours were a bit of a test field. To cut a long story short, our initial system was not powerful enough. I know that sounds daft; we’re in Spain right? The sun shines 365 days a year. But it doesn’t quite work like that. The level of consumption we were accustomed to in the UK was way above what the local Spaniards used. So our solar installers looked dismayed when we unpacked our electrical appliances. Our reassurances that some appliances were used for a few minutes once a week did not ease their concerns. We learned to operate the system from the Mate controller in the house [above], sister to the master Mate in the solar casita. It enabled us to see the level of power in the batteries, and the amount of energy being gathered from solar and wind via the invertors [below]. Simple things were done straight away to reduce consumption. All light bulbs in the house were changed to low-voltage, dimmer and two-way switches removed. My hairdryer was repacked in its box. Mobile chargers were unplugged after charging. The electric kettle was put away and a whistling kettle purchased. The air-conditioning units would be used as a luxury, we decided, though we soon learned that the house is blissfully cool in summer so in truth the air-con is rarely needed. Now, we know our usage thanks to this handy monitor [below]. In the beginning, we learned the hard way. That first winter we got used to power cuts and candles. Our back-up systems – windmill and generator – ran well enough, but we simply didn’t have enough solar panels to charge our enormous battery pack [below]. And then the price of diesel started to rise. A solar consultant analysed our system and presented us with a plan to overhaul everything. His suggestions were ingenious, highlighting problems we hadn’t realised were problems. Problem one. Our water is spring-fed not mains. When we arrived we had installed a 25,000 litre tank to store water in case of drought. This was done with the best intentions, but we chose the wrong place to put it. The large tank was positioned slightly downhill which meant that every time a tap was turned on in the house – to rinse a cup, wash hands, fill the kettle, flush a toilet – the water pump activated to move the water back uphill. The solution: a small pressurised header tank installed beside the pump to feed the house system using a fraction of power to do the same job. Now, the header tank fills from the big depósito only twice a day on average. And, of course, our spring never has dried up!
Problem two. The biggest consumer of electricity is the swimming pool pump which must run 4-6 hours a day in summer to churn the million litres of water. The solution: a separate solar-powered pump. This ticks over gently when there is enough solar electricity generated by the three panels mounted out-of-sight downhill on the pool wall. When the solar pump is still, the conventional pump clicks into action.
Problem three. Our solar equipment – batteries, panels, invertors, master controls and generator – are housed in a little casita up the hill from the house. The layout of the controls was rationalised to improve efficiency, the three invertors overhauled and re-organised. All cabling was checked and upgraded, with the addition of a 10-point hub. Ventilation in the casita was increased. At last our BMW-like German solar batteries have enough solar energy to fill them, and the generator [above] runs so infrequently that we require only one delivery of diesel a year to fill our huge diesel tank [bottom]. Problem four. Not enough solar panels. This one was easy. We added another 15 panels, fixed on the roof of the solar casita, not a problem as the placas are made in China and so very cheap.
The review and subsequent work took a year to finish. The result? We now have an efficient solar system like the one we thought we were getting in the first place. Technology since then has improved radically, prices have fallen and efficiency improved. The experience of consumers like us has informed the solar consultants in terms of planning installations. Oh it is nice to be a guinea pig! 5 to remember
una placa solar – a solar panel
la elección – choice
independiente – self-sufficient
un apagón – blackout [power]
el subsidio – government grant