Malls, schools lead in use of solar energy

More people are awakening to the fact that powering, heating and cooling homes and offices using conventional energy is expensive. This realisation has seen renewable energy gain popularity.

The world is also gearing towards ensuring access to affordable, reliable, sustainable and modern energy for all. Solar power is one type of renewable energy has been well received. The International Energy Agency predicts that by 2050, solar energy will be the number one producer of electricity in the world.

For instance, in the United States, every three minutes, someone switches to solar energy. Closer home, Uganda commissioned a 10MW solar project. The $19 million (Sh1.9 billion) consists of more than 32,680 PV panels and will provide power to more than 40,000 households in rural Eastern Uganda.

Locally, the reception rate may not be that high but the transition is going on. Individuals, big firms, developers and institutions are having enough of the soaring energy prices and switching to solar power. We have witnessed major solar projects in the country.

A good example is the Two Rivers Mall solar project, which is expected to produce about two megawatts. The mall will be powered by an advanced solar technology, which will be complemented by power from Kenya Power.

pv power

Over 150 solar panels have been installed with a smart intelligence system that optimises the PV power churned by the system to the grid.

The system quickly detects any malfunctions as a result of low power produced and a panel can be replaced without interfering with the rest. The solar system seamlessly integrates with grid and diesel generator and optimises the solar energy generation to meet the consumption load.

During the day, the solar system is given priority, enabling the mall to reduce its energy bill by 30 per cent.

Another remarkable solar project is the Garden City carport. A carport is a wall-less shelter for cars consisting of a roof supported on posts. Solar carports are gaining popularity worldwide because they make use of otherwise functionless rooftops.

The Garden City solar carport has over 3,300 solar panels that generate 1.26 megwatts per year. The project was installed by Solarcentury, a London-based solar firm. It provides clean energy to all the retail tenants at the shopping mall.

Developers are also turning to solar energy. Strauss Energy, a firm dealing with solar roofing tiles, has partnered with a real estate firm in a mega project in Kitengela. The project involves roofing of 700 houses in a gated community with the solar tiles. This will achieve a one megabyte solar power system to power the estate.

The energy firm also has ways of storing the excess power from this system, with the option of sending power back to the grid.

“We use a technology called compressed air energy storage that has batteries that can serve the client for 30 years as compared to typical solar batteries that last a maximum of two to three years,” says Charity Wanjiku, the chief operations officer of Strauss Energy.

For institutions, Strathmore University leads the pack, being the first university in Africa to have the largest solar panel rooftop. The institution boasts a 600-kilowatt grid connected solar PV rooftop with over 2,000 panels. The project, funded through a subsidised loan from the French Government, was completed and commissioned in 2014. The solar system caters for all the electricity needs of the university. The excess power is supplied to the national grid at a fixed pre-determined rate.

Recently, Starehe Girls Centre won an international energy award for its proposed solar project. The school plans to implement a rooftop photovoltaic system that will reduce the institution’s utility bill by 20 per cent.

constant sunshine

The principal, Sr Jane Soita, says: “The project entails installation of a 25-kilowatt photovoltaic rooftop system, four solar water heaters and 10 solar powered street lights. Although Kiambu doesn’t have constant sunshine, the sun-length we experience will sustain the system. The project will help us reduce our utility bill by 20 per cent and we intend to use the savings to enrol an additional 10 girls in the next academic year.”

Solar energy has challenges, though. Nickson Bulachi, a solar energy expert, says that clean, renewable energy is the future and with the rapid growth of solar market, solar has the possibility of becoming a primary energy source.

He says solar is a clean source of energy as it is void of carbon dioxide and other emissions synonymous with most of the fossil fuels. For that reason, it helps mitigate the effects of climate change.

Additionally, solar is a more affordable source of energy because it is generated naturally by the sun.

One setback is storage. “Solar energy is mostly available during the day and hence needs storage or back-up for use at night. Most of the storage technologies available in the market are very expensive. Storage increases cost by more than 60 per cent of any installation,” says Bulachi.