Canal-top PV will save water and produce clean energy in Gujarat, India

1 MW of Canal-top solar power in Gujarat, the western tip of India, promises to produce power and prevent water loss.

Gujarat is the small, westernmost state in India, home to over 60 million people, many of which are without access to electricity or water.[1]

The national electrical grid in India is unstable and inefficient. During transmission and distribution, it loses 22% of what it generates in centralized coal, hydroelectric, natural gas and nuclear power plants.[2] India’s grid remains chronically short on generating capacity and has a history of massive power failures (July 2012 blackout in India left 10% of the world population without power)[3]. It also does not extend to the remote, western parts of India.

Water supply is also a problem in Gujarat. With relatively low rainfall and a semi-arid to arid climate, Gujarat has poor surface water resources. In an effort to bring water to rural districts, the state developed a massive web of concrete and cement-lined canals, diverting water from the Narmada River for irrigation and drinking water purposes for thirsty, growing populations. However, due to extreme heat and dry conditions, much of this water is lost through evaporation.

Gujarat has a semi-arid to arid climate, but is also has the country's greatest solar resources

Gujarat has a semi-arid to arid climate, but is also has the country’s greatest solar resources

Not surprisingly, the state of Gujarat has immense solar power potential. It has some of the strongest solar resources in the country. By installing solar PV panels atop the Narmada canal, nearby Gujarat residents will have access to reliable off-grid power that simultaneously prevents water loss through evaporation by shielding the canal’s water from sun and wind.

This suspended system is the first of its kind since it is mounted over a water canal. It spans about a kilometer of the canal, but does not touch the water. Solar Edison was commissioned in 2010 to engineer and construct the project. Their design includes 1 MW of power over a narrow strip of one of the canal branches since the main Narmada canal is extremely wide. The site was selected because there are reliable roads and access to the electrical grid nearby. The canal also runs North-South, which maximizes the amount of sun that shines on the panels and therefore, the amount of power produced. An added benefit of installing panels over water is water will keep the panels cooler, which improves PV efficiency. Solar panels over water will end up producing more power over a longer lifespan than panels mounted on land in extreme dry conditions.


Solar Edison’s design promises to save an estimated 7,000,000 L of drinkable water per year by preventing evaporation and preventing algae growth in the canal. Algae can clog the irrigation pumps, which increases maintenance costs and lowers productivity.[4] The state appreciates that this system both will generate clean energy and conserve water. They also appreciate that it does not require new land acquisition. The next proposed phase of this project will double the solar power capacity installed over the canal to 2 MW.[5]


[2] Electric power transmission and distribution losses (% of output), World Bank, 2010 estimate <;

[3]  NY Times: “2nd Day of Power Failures Cripples Wide Swath of India” July 31, 2012





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7 responses to “Canal-top PV will save water and produce clean energy in Gujarat, India

  1. oscargarcia003

    This innovative accomplishment seems to clearly take out two birds with one stone – the birds being water conservation and electricity generation, and even added benefits. One of my first thoughts was about the risk of damage from weathering or storms to the panels. I suppose they would assume similar risks as would any other rooftop panels, aside from seasonal or freak torrential flooding perhaps? How can this be applied to other regions with similar or even not so similar characteristics of climate and infrastructure? I would think that covering up canals with PV could be quickly adopted in the states as we may have more adequate resources for such a project. Large solar farms as this would surely require major capital costs, with assistance from all levels of involvement. Like the vast arrays set up in the southwestern states, these projects would not be done without due hurdles over red tape, etc. Who would need to spearhead the efforts? Municipalities and states would surely need to, and this may be an appropriate way to pilot impact investing projects with the private sector as well. I am very eager to see how this serves the community in India in the coming years.

  2. enesgokkus

    This is a great way of combining power generation and water saving in one system. At first glance, one might argue that water saving by enabling less evaporation may not be significant. However, it is claimed that 7 million liters of drinkable water will be saved each year, and that number is extremely important for that hot and arid part of India. As reported in the case study, evaporation consists of two stages: vaporization of water particles by heat coming from sun and traveling of these vaporized particles by wind. The solution is perfectly simple; flat solar panels installed on the channel enable both utilizing the high amount of heat into useful form of energy and breaking the wind on the water channel. Moreover, algae formation is prevented. What works better to save clean water while generating electricity? It is important to state that applicability of this project in other parts of the world depends on regional conditions. Environmental effects such as ecology and climate dictate modifications in design, which may increase the cost of installation and operation. However, considering the fact that that part of India does not bear risk of tropical storm and flooding of the river, structural design and safe operation are not the main challenges there. The bottom line is that this project is a good example demonstrating that energy solutions do not have to be complicated; simple ideas like this could serve the communities effectively. I hope this project will be the first of many others worldwide and encourage the flexible design of renewable energy systems for land-specific conditions.

  3. Pingback: Strategically Placed PV | Energy, Technology, & Policy

  4. This is a very innovated solution to solve two infrastructural issues at once. The economics of the project don’t seem too poorly skewed since the added cost only between 20-25% higher than a standard system. The side that amazes me is that by installing the system over only a 1km long stretch of canal they could save over 7 million liters of water annually. It seems that since water scarcity is a much larger life threatening issue in the region, they could expand the project to the wider parts of the canal, even only implementing a system to conserve water since the panels are not able to span that distance. It is encouraging that such critical problems can be solved with such simple creativity!

  5. It’s great to see a solar panel project providing multiple benefits in addition to providing a new source of energy generation. Similar multi-benefit projects can be found in the U.S. Take for example the Santa Rita prison in California. The prison holds 4,000 inmates and has an annual utility bill of $3 million. Chevron Energy Solutions helped install a solar system that is generating savings as well as electricity. Perhaps more importantly, the PV system allows the prison to isolate itself from the grid in an emergency and operate via its energy storage system. This is especially important because the prison cannot afford to lose power.

    Solar projects are also going up in California’s public schools and while providing energy savings, the projects are also teaching kids about solar and environmental projection. You can read more here:

  6. Pingback: Solar Panels and Airports, like Peanut Butter and Jelly | Energy, Technology, & Policy

  7. Pingback: Canal Solar em Gujarat irá produzir energia renovável e evitará 10 milhões de litros de água evaporada por quilômetro – Fotovoltaica Energia Solar ®

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