It's been a long and at times rather slow journey, but we are finally producing our own electricity!
A surprisingly small but pleasingly heavy box sat in the porch when I arrived home from work a week or two ago. I unpacked the turbine with great excitement. It is beautifully made, my Stream Engine, with its cast alloy casing, tight coils, chunky magnets and bronze turgo wheel. This wheel is only 5 inches across, and with the fire hydrant flow thundering out of the penstock I wondered how on earth it could capture all that water and all that power.
I managed to pilfer a couple of concrete blocks, cemented them down on their sides, and bolted the turbine on top. From the four way manifold I wrestled four lengths of 2" flexible hose into place, supplying each of the nozzles. These terminate in brass nuts drilled with a 5mm hole, each firing a jet of water directly at the cups of the wheel. Energy Systems and Design, who I am more than happy to name check, sent a selection of these nuts with nozzle sizes ranging from 2mm to 10. We will experiment with these to eek the maximum juice.
Once the plumbing was finished it remained only for me to rudely ignore numerous newly arrived guests, who seemed not to share my single-minded enthusiasm for the imminent realisation of a long held dream. I nervously connected up the cable. Hannah and the children back from school, it was time to release the flow. The family gathered around the door of the turbine house. I turned on the valves. With a mighty roar of water the turbine spun into life, sending the numbers on the voltmeter racing up!
After a day or two the whistling from the turbine quietened down, and now the loudest noise is the rushing of the water. This in itself is not quiet. In the turbine house itself (actually Gordon's old garden shed, more recently our pig house, now plonked on top until we build something better in the spring), it is deafening. But the swine bashed panels hold most of sound in, and I like to hear the energy anyway. Electricity is usually so silent in our homes.
As I feared the power is making only a small difference to our heating. The oil fired boiler is rated at 20-25 kW. Although I have yet to measure the wattage, the turbine is likely to be producing around 0.5 kW, fifty times less. Heating our homes and hot water require huge amounts of power, making lighting and appliance consumption seem slight. Our hydroelectric system is a better match for the latter, and with the PV system we are now planning, could supply most if not all of our needs. Heating will be better met with the wood stove and boiler, to which end we have just built another lean-to shed, ready to store the vast amounts of wood required!
It takes truly scary levels of power production to supply the needs of a 21st century home, and for most of us it simply comes with a flick of a switch and a quarterly, and currently largely affordable bill. I am beginning to stop taking this for granted.
