Monday, August 25, 2008

Water tanks use less energy than desalination

John Brumby and Tim Holding would do well to consider mandating rainwater tanks for new houses rather than building an energy guzzling desalination plant.

Our domestic water tanks have supplied over 95 per cent of the water for our Surrey Hills house since we installed them in 2001. Based on our experience, 600,000 households could save up to 160 gigalitres of water per year by using captured rainwater and reducing their daily consumption. The energy our pump uses would multiply to 140 kWh of energy per day for these same households. The proposed desalination plant would consume 15 times as much energy just to operate.

There would also be significant emissions associated with the construction of the plant, the pumping of water to Melbourne and waste decomposition and transport.

Domestic water tanks would be a much cheaper, more effective, more greenhouse friendly and more popular solution to meeting Melbourne's water needs than either the proposed desalination plant or the north south pipeline projects.



Anonymous said...

Methinks the lobotomised people in charge of managing our water need to have their their heads twisted back the other way.

Anonymous said...

Hi Peter,

Am almost in total agreement with the direction you put forward above. As an ex-town planner, to me the main issue appears to be the Govt's ability to retro-fit existing homes with rainwater tanks in a quick enough timeframe to circumvent the need for augmentation of supply.

Whilst I would support the planning / building regs being amended to make rainwater tanks mandatory for new development, in reality "new development" is not going to solve the problem. If we are talking about 600,000 households in a reasonable timeframe, then the majority of these are going to have to come from existing dwellings. What is the ability of the Govt to intervene (in a short to medium timeframe) in people's backyards and force them to install rainwater tank systems? I think this is the key issue that the Govt would be grappling with.

Thanks for your research.