During our Eco House challenge for electricity we determined that for Autumn, Winter and Spring, that our average daily usage was 14 Kilowatt hours (kWh) per day. Not bad for a family of six, I thought as the daily Australian average was 16.44 kWh. Still, I knew we could do better than that. As over 90% of Victoria’s electricity is generated by brown coal which vomits 1.2 Kg of CO2 into the atmosphere for every kilowatt hour generated, we had changed to GreenPower from Origin Energy in January 2007. They had a deal at the time, whereby if you stayed on GreenPower for 12 months then you would receive one months free electricity in the 13th month. It was a good start, but I yearned for more. I wanted to generate my own power from renewable sources.
I set myself a goal that I wanted to generate at least 65% of our own power, and I believed that as the kids began to leave home (one can only hope!) then our energy consumption would drop and the total percentage of generated power would rise. That was the theory and the long time plan.
I researched extensively on the subject of renewable energy, and studied Photovoltaics (PV), Wind, Mini Hydro (I was thinking of what to do with the pool water in winter), and even had a look at steam power! I figured that my house was best suited to photovoltaics as I had the roof space and did not have the land are that wind required or suitable conditions for wind. Besides, I didn’t want my neighbours taking pot-shots at a noisy wind turbine.
Now that I had decided on PV grid connect, I had to figure out how size of the system we required to hit my 65% goal, and how much we could afford. To determine this we need to find out how many peak sunlight hours we received in our area. The Government “Technical Manual – design for lifestyle and the future” was a good resource for this type of thing and I discovered that we received about 4.6 peak sun hours. We live about 50 Km west of Melbourne, and have less rainfall than the city, so I was hoping that the peak sun hours would be more like 5 for our area. So all I had to do was multiply peak sun hours by the kilowatt rating of the system and you get the average kilowatt hours produced by the system per day. So as I needed about 14-15 kWh per day, I calculated that we needed a 2.8 kW PV system (5 * 2.8 = 14). I now asked for a quote from three installers and they ranged from $30,000 to $40,000. The $30,000 quote came from a company called Energy Matters based in South Melbourne. I was the first customer from Melton! They came and did a site survey to see if they could fit a system that large on my house, and told me that I could only get about 6 panels on the main roof. However, they could fit about 20 on the garage roof and it had a northerly aspect with very little shading from trees. With that settled and the quote firmed up, all I had to do was find the money!
I was aware of the Federal Governments decision in the 2007 budget to increase the PV rebate from $4 per watt up to 1kW to $8 per watt up to 1kW. So therefore I would receive back $8000 as a rebate. That was $8000 less I had to find. Also I discovered that my system would generate enough renewable energy to receive about $1400 in Renewable Energy Certificates (REC’s), which I could sell on the market. So the total amount I had to borrow was $20,300 to pay for the system. Energy Matters said that they would take the PV rebate as part of the payment and all I had to do was sign the rebate over to them after installation. I also was entitled to discount of $300 as I was a member of the Alternate Technology Association (ATA). By being a member I also received a subscription to “Renew” magazine which focuses on renewable energy systems. It also helped me understand what I was getting into.
I managed to successfully apply for a personal loan after a lot of hassle with one of our banks, and received a small interest rate discount for being a staff member. I paid the deposit and applied for the PV rebate via Sustainability Victoria in the first week of July 2007. Energy Matters told me that it would probably take 6 weeks for approval, however, Sustainability Victoria replied back within 5 weeks with the approval to go ahead. There was a slight delay after the approval because all of the components had to be sourced from Japan and Germany. I thought at the time, why couldn’t the equipment be manufactured in Australia? Apparently, reliability is the issue for outdoor system. My grid connect inverter would be exposed to the elements. I did find this hard to believe!
Anyway, the installation date was set for August 25th, and after many frustrating days of waiting, the day finally arrived. I took the day off of work so that I would watch the installation. it was a very cool and windy day and the wind got stronger as the day went on. The three installers decided to postpone putting up the panels until later on in the week and we all agreed that this was for the best as I didn’t want any of the guys flying off of the garage roof like a kite holding on to a panel. However, they worked tirelessly to ensure that all of the frames for the panels and all of the electrical work was completed on the first day. This included the installation of the Fronius IG 30 grid connected inverter. The next window of opportunity was the 4th of September. They had everything ready to go and I even stored the 175 Watt Sharp Solar panels in the shed for a week.
The final day arrived and it was a wonderful sunny day. Two installers returned as promised and it took them most of the day to fit the 16 panels and to wire them up to the junction box on the roof. At about 3pm, it was installed in its entirety, and I had the gracious honour of throwing the main breaker. It was a wonderful feeling to watch the inverter start up and then synchronise with the power grid. It registered 1850 watts at that time of day. We all ran over to the electricity meter in the main switchboard, and sure enough the meter was spinning backwards as we were not utilising that amount of power at the time. I was elated!
I thanked James and Jan and after they had packed up they departed. I must have stared at the display on the inverter for about 30 minutes when I had a brilliant idea. I raced inside and presented a chilled bottle of Rose and two glasses to Kim, and we toasted the PV system and the power of the Sun. We both were ecstatic and stayed in the garage until sunset and watched the inverter power off. We went to sleep that night very happy with ourselves.
Over the past 7 months we have generated 2.3 Megawatt hours of clean electricity and are producing 64.3% of our own power needs. When we reach the 1st anniversary of the system we will have a better indication of our generating capacity. It is in the Summer months that we consume the most due to air-conditioning, ceiling fans, and longer operating hours for the pool pump. I believe that we will ultimately generate between 75 and 80 percent of our electricity needs, but only time will tell.
On a final note, the PV system has had an unexpected effect on all the family. By generating our own energy, we began to respect all of our power usage much more than our simple effort of energy efficiency. Lights and appliances began to turn off without a word from me, and the kids all became power savers instead of power wasters. All a fantastic effect if you ask me as all family members are now energy conscious!