By Celsias Team
As well as having an impact on wildlife, hydro dams don’t last forever, and their decommissioning can cause built-up toxins in sediments to be released, a process which author K. Gregg Elliott says could lead to carbon release in the atmosphere (read the article here). But many still herald hydro power as a renewable source of energy and according to new research from Scientists at Plant & Food Research, New Zealand’s hydroelectricity has a better environmental footprint than many other countries.
According to the science company, the water footprint of our hydroelectric power stations, in most cases, is only slightly positive or even negative. It says research also showed that the dam and reservoirs associated with hydropower stations in high rainfall areas of the North Island do not adversely affect the amount of water available for use downstream.
Research by PhD student Indika Herath in Dr Brent Clothier’s Systems Modelling Group at Plant & Food Research has measured the water footprint of hydropower generation at 17 hydroelectric stations across New Zealand as part of a research project to calculate the production footprints of New Zealand’s plant and food products. The research, published in the Journal of Cleaner Production, shows that the water footprint of hydroelectricity generated in New Zealand is lower than the international figure routinely used.
In the North Island, hydroelectricity generation has a negative water footprint, with the presence of a reservoir not decreasing the amount of rainwater entering downstream river systems.
“It’s important that we reduce water use wherever possible and developing water footprints for each step of a production life-cycle is one way to help us accomplish this, allowing us to assess hot-spots of water use and economise where possible,” says Clothier.
“Electricity is a key component of any food product’s environmental footprint, used in powering irrigation and other systems on the farm, through to packaging, processing and storage of finished goods. Whilst greenhouse gas emissions and the carbon footprint of hydroelectric power is smaller than that of most other fuel types, international evidence suggests that it has a larger water footprint. Our research shows that New Zealand hydroelectricity has a much lower water footprint than the global average.”
In fact, Clothier is so confident about the findings, he goes as far as to say it “reflects our brand image of ‘clean and green’”. A brave claim.
