I applaud national water agency PUB's idea to test energy yield from Tengeh Reservoir to evaluate the feasibility of tapping renewable electricity using floating solar photovoltaic (PV) systems (Siting solar energy farms at reservoirs; Sept 30).

This effort to boost the electricity supply using Singapore's reservoirs is pragmatic and productive.

Moreover, having the solar panels cover the water surface will not only reduce fresh water evaporation, but also help to cool the electronic units.

There are other factors in Singapore's favour for renewable solar energy.

The Republic is just about one degree north of the equator and has, on average, 12 hours of sunlight a day. This translates to more than 4,000 hours of daylight a year.

The world's largest floating solar farm is in the Chinese city of Huainan in Anhui province, where a tapestry of 120,000 solar panels covers an area of over 86ha, generating 40MW of power, enough for 15,000 homes.

From the crude data, it seems that each hectare could power over 174 homes.

The surface area of Singapore's reservoirs is substantial.

If the reservoirs were deployed to host floating solar farms to produce renewable energy, it could power a large number of homes.

For instance, if the total reservoirs' area were 1,500ha, the potential renewable energy could power over 260,000 homes.

This projection is based on the 15 per cent to 20 per cent efficiency of solar panels. If high-efficiency PV systems with 44.5 per cent efficiency are available, the energy generated could be doubled.

Singapore has no large desert, lake or wind power to create more renewable energy to help fulfil our climate change pledge.

Floating solar farms at reservoirs are a good alternative and, indeed, Singapore's best hope to generate electricity without air, water and land pollution.

Paul Chan Poh Hoi