Panel Your Canal

In a world that is shifting away from the use of fossil fuels, a top priority is finding new, innovative ways to conserve and create energy in the renewable energy space. Solar canals are one of the latest innovations driving positive change in the race to net-zero by 2050, and various countries are eagerly getting on board.

The case for Solar Canals

In response to what is shaping up to be the worst megadrought in the U.S for the last 1,200 years, researchers at the University of California have developed the ‘solar-canal solution’. Project Nexus is a $20 million project to build solar panel canopies over the Turlock Irrigation District canals, expected to be complete in 2024.

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Described as “covering canals with solar panels”, the University’s 2021 study found solar canals can result in multiple benefits for water and energy infrastructure. Most notably, in the context of California, solar canals may reduce evaporation of water canals by up to 82%, or approximately 286 billion litres of water a year. This is enough water to irrigate 50,000 acres of farmland or provide 2 million people with an adequate water supply. At the same time, the solar panels can generate enough energy to account for a sixth of the state’s total energy needs.

While a potential disadvantage of solar panels is the cost of installation and upkeep, the design of solar canals ensure they are a long-term investment. The canal creates a cooler microclimate for the solar panels, allowing them to perform at maximum capacity for a longer period.

Solar canals may also relieve concerns that renewable energy infrastructure takes up land that may be used for other purposes, such as farming or residential homes. Instead of separate solar farms, panels are installed directly over canals, thus maximising efficient use of space.

International context

Countries such as India and France, and even companies such as Coca-Cola have implemented solar canals as part of their renewable energy schemes and infrastructure.

The French are buying into the solar canal innovation with Societe du Canal de Province and the energy provider Sergies signing a partnership agreement to jointly finance, build and operate four solar PV systems with an aggregate capacity of 12 MW on the Provence Canal. The Provence Canal provides water to 110 municipalities in the southern French regions of Bouches-du-Rhone and the Var which include major cities such as Marseille and Toulon. The two companies have estimated that the Provence Canal could potentially play host to approximately 40 MW of solar PV capacity.[1]

In India, the Jharkhand Energy Development Agency is tendering for a MW scale solar canal project with the successful proponent expected to conduct site surveys for canals that can be utilised for grid-connected solar PV. In 2012, Gujarat State Electricity Corporation and Sardar Sarovar Narmada Nigam Limited commissioned a solar canal project that included a 1 MW plant covering 750 metres of the Narmada canal. It was projected that the solar PV panels would prevent the evaporation of approximately 9 million litres of water per year.^[2]

Australia’s irrigation canal system

The World Resources Institute ranks Australia as a country with medium to high water stress.^[3] One does not have to look far to see the devastating effects of water scarcity that parts of Australia has endured during certain periods in our history. Water scarcity can have a significant impact on our agricultural sector, much of which is reliant upon the health of our water systems and the major irrigation areas that such systems feed. Australia is home to extensive canal systems that supply water to Australia’s largest irrigation areas. The Murrumbidgee Irrigation Area has about 3,500km of canals, the Murray Irrigation includes 3,000km of canals and the Goulburn Murray Water area in Victoria has about 7,000km of canals.^[4] Leakage, seepage, and evaporation from delivery canals all contribute to significant amounts of off-farm water losses, which is estimated to be 130 billion litres  per year in the Murrumbidgee valley alone.^[5] Investment in piping or lining canals could help prevent off-farm evaporation, but the costs of undertaking such improvements are prohibitively expensive.  This provides an opportunity to implement proven solar canal technology to reduce canal water evaporation and improve solar PV panel efficiency.

The development of solar canals marks the newest chapter of innovative renewable energy solutions and demonstrates the world’s capacity and resilience to innovate our way to net-zero by 2050. The message is clear – Australia should draw on international experience in solar canal development and capitalise on the vastness of our in-land waterways to increase renewable generation and conserve scare water resources.