How to connect the Australian electricity grid with renewable power generators:
Renewables Grid Connection – from AEMO report on generation of 100% renewable energy for Australia
Australia’s size and vast, largely unused, spaces provides both an incredible opportunity as well as a challenge for power transmission. The AEMO study explores this at detail and already recommends the use of High Voltage Direct Current (HVDC) cables for long distance transmission. This technology is already used to transmit power from Tasmania’s hydroelectric power plants to Victoria across the Bass Strait. At 290km, the Basslink cable was the longest submarine HVDC cable in the world when it was built and in 2013 is the second longest; The NorNed cable connecting Norway to the Netherlands is 580km long. The Basslink cable also includes a fibre optic link, which shows that a project to transmit power from remote locations could also be used as a communications hub to connect Australia with high speed data links.
Australia has two other long distance HVDC connectors in operation in 2013. The Terranora link that joins the Queensland and New South Wales grids across a 59 kilometre gap and Murraylink that joins the South Australian and Victorian power grid across a gap of 180 kilometres. Murraylink in 2013 is the world’s longest underground HVDC cable. So Australia is no stranger to this technology and has been at forefront of deployments globally with two record holding lines. However, other countries have already deployed far longer overland cables, most notably China and Brazil. China currently holds the two longest HVDC cables, each around 2000km and the second built, the Jinping-Sunan line is the highest power transmission line in the world with a 7.2 gigawatt rating (7,200 megawatts). Both of these will be superseded by the Rio Madeira link in Brazil when it is fully commissioned in 2014 at a length of 2,375 kilometres.
Having established the length and capacity of HVDC links that have already been constructed, it shows that Australia has every reason to make use of otherwise unusable tracts of the country to generate vast quantities of solar, geothermal and wind power, knowing it can easily transport the energy to the existing National Electricity Market that connects the state grids of South Australia, Victoria, Tasmania, New South Wales and Queensland. The Australian Capital Territory (ACT) is considered a part of the NSW grid. As a result of the large distances and relatively low demand, the Northern Territory and Western Australia each run separate power grids.
However, adding fibre data links to the cable laying process is only just the beginning of the potential to be explored. The construction of high speed rail links connecting Brisbane, Sydney, Melbourne and Adelaide is becoming an increasingly high demand infrastructure project to deal with a post fossil fuel world. Making these new transport links run electric trains provides two opportunities, firstly we gain a high speed transport infrastructure that can shift the demand from air transport and secondly, the project that lays the rail lines could also lay HVDC cables and fibre data cables as well as the power lines needed by the trains. This could provide multiple redundant high speed data and electricity links across the country, as well as powering the new transport entirely from renewable energy sources. The extra power demands of the train system could easily be generated along the length of the track with dedicated generating plants that could also be grid connected as required.
Placing these plants in outback Australia provides another windfall for farmers and landowners. They can earn guaranteed rental income by hosting plants on their land. This has already been established through existing wind farm deals, where the landowner receives AUD$8,000 a year per turbine. These deals could be modified and expanded to cater for multiple solar thermal plants that could provide guaranteed annual income for farmers; regardless of weather, crops or herd conditions. In a country assaulted by droughts and floods on a regular basis that have driven many farmers to bankruptcy, this could be a lifesaver that also greatly reduces the need for government assistance in hard times. This means farmers can get on with their jobs and government can spend time and money looking at bigger picture projects such as Murray Darling water catchment and the national rollout of renewable energy and transport infrastructure including the new transmission lines.