January 22nd marked the end of nine months of recording the performance of the Greeny Flat in its first year. As you can see from our Results Table, things are going very nicely and we are on track to meet our original goals.
To sum things up, overall:
- we’ve exported (put into the electricity grid) more than three times as much energy as we’ve imported (taken from the grid)
- we’ve used about 6700 more litres of tank water (harvested rainwater) than town water
- and the interior temperatures have stayed pretty comfortably within a 16degC temp variation compared to an exterior temperature swing of 45degC.
Five times more Export than Import over the last three months.
During the colder, less sunny months (May to October) we managed to consistently export 2-3 times as much power as we imported. Still we’ve been quite amazed to see that over the last three months (Nov to Jan) we’ve exported 1187kWh and imported only 228kWh. In other words we’ve put more than five times as much electricity into the grid as we’ve taken out… wow!
The challenge for us going to into the future will be to find ways to use that excess energy to replace more of our overall fossil fuel consumption. We don’t plan to make any big changes until we’ve completed a full year of testing the Greeny Flat. Earth Day this year (April 22nd) will mark the end of our first year and at that point we’ll be looking to take the next step(s).
We’ll be looking closely at our food choices where there is a great deal of hidden energy consumption but the obvious thing for us to do next will be to try to replace more of our car usage with sustainable forms of transportation. We already walk or ride our bikes for a lot of the things we do in town like shopping, going to the post office, going out to a restaurant, etc, but one of the disadvantages of living in a semi-rural area is that things are pretty spread out and there is not a consistently reliable public transport system.
For some of my work I have to drive to the next town. My parents live about 15km away on the other side of a pretty big hill so riding a bike there would be a challenge. Even going to our tango classes in Bowral would require a pretty fair commitment on a bike. So we’re looking into options for either an electric car or electric scooters that we could charge from our solar power system and use for a lot of our local running around. One possibility might be for both Cintia and I to get something along the lines of the Mebike pictured below. This is an Australian designed, decal-assisted electric scooter which costs around $1300 new.
Alternatively we might look into buying an electric car (for a LOT more money) but my feeling at the moment is that battery technology isn’t quite up to speed yet although it will be very soon. I think in the next few years we’ll see tremendous advances in the area of electric vehicles so I’m inclined to not spend too much money right now. Scooters would be a decent (and affordable) solution for now and, hopefully, in a few more years we’ll be able to buy something like the UNSW “Sunswift” solar powered electric car pictured below. Affectionately known as Eve, she has a range of 800km and a top speed of 140km/h… not that we need to go that fast but she does look like fun. We’ll keep you posted as things develop.