Cooking and hot water is provided by LPG and his 5kW Villager wood burning stove means that despite being in one of the windiest parts of the UK, winter nights in are cosy and warm.
With average wind speeds of 8m/sec in the summer, rising to 12m/sec in the winter, Derek choose the Extreme version of the LE-v150, specially adapted for high wind sites where winter storms render horizontal turbines useless as wind speeds of up to 100mph have a tendency to shake small wind turbines into small pieces. Derek mounted the LE-v150 Extreme on a 10m tower to catch as much wind as possible – this turbines comes into its own during the winter when the irradiation levels are low and the solar panels provide little electricity to run the home.
“While I was researching products, Leading Edge provided an amazing amount of information and explanations of off-grid design," Derek continued. "I can say that I have always been incredibly impressed by Leading Edge, the support and information is second to none.”
During the winter months, the turbine delivers electricity for lights, tv, hi-fi, alarms, sceptic tank pump and for charging laptops. In the summer, the combination of solar PV and wind turbine generates so much power that Derek was throwing power away in the afternoon so he now has a 650W electric kettle and a 120W slow cooker to soak up any excess power and reduce LPG usage.
Off-grid living does require a bit of adaptation. Derek chose wooden floors so there was no need for a vacuum cleaner, instead a mop does the trick! Hot water for a shower and kitchen/bathroom hot water tap is provided by a Morco Super Compact F11E 11 litre per minute LPG boiler. It is the sort of boiler for a mobile home or caravan.
Currently Derek doesn’t have enough power for a washing machine. “I soak clothes in hand wash soap powder – getting them dry is fine during the summer but difficult in the winter when we have our strongest storms. Washing lines are not that good in very high winds so I’m looking at a spin dryer. There is an Indesit spinner that only uses 240 watts.”
Derek also doesn’t have the power for a fridge or freezer. Living on an Orkney Island means temperatures never get too high. “I am investigating developing world methods of preserving food, the ‘pot in a pot’ method is possible where clay pots are placed in water and evaporation cools the contents,” concluded Derek. “Compared to the rest of my set-up here, it’s a relatively low tech solution but if it works then that’s what counts!”
Along with the LE-v150 wind turbine and solar panels, the off-grid power system comprises an MPPT regulator, two 120Ah gel batteries and a Victron inverter/battery monitor. Power from the wind turbine and solar panels is fed into the batteries and then taken through the inverter into the mains.
“The batteries I chose are Gel type because I have a large garage and want to work in there, so ordinary lead which produce gas was not an option,” said Derek.