Kenyan firm beat Tesla to solar roofing tiles

When Tesla announced their ‘groundbreaking’ innovation of a solar roofing tile in late October, the tech world went gaga.

Few people knew that Tesla had been beaten to the punch by Kenyan firm Strauss Energy.

The buzz was for a good reason. Solar energy is gaining popularity as the world gears towards ensuring access to affordable, reliable, sustainable and modern energy for all.

This has led to innovations in the energy industry. One Kenyan company on the bandwagon was Strauss Energy.

The company integrates energy-generating technology into basic building materials to ensure access to clean energy.

Strauss Energy brought a new technology on solar-power roofing tiles into the market.

Initially, people using solar energy only had the option of having solar panels mounted on rooftops. Not anymore. This innovation serves the dual purpose as a roofing material and as a solar panel.

The idea of solar tiles was born through a class project by Tony Nyagah, the firm’s CEO, an engineer by profession.

“Nyagah conceived the idea as a project for his masters class and the architect in me helped him in perfecting the design of the tile. He is the co-founder and chief executive of Strauss Energy,” says Charity Wanjiku, the chief operations officer at Strauss Energy. Nyagah is Wanjiru’s elder brother.

Wanjiku says their innovation integrates the solar panel into the roofing tile, allowing developers to construct their houses without worrying about the need to create allowance for installation of panels on their roofs.

The two-in-one tile also allows a roof to maintain an appealing design.

“Traditional photovoltaic solar panels detract the aesthetic of a roof, something many homeowners dread. Our tiles enable you cut on the cost of energy as well as maintain the beauty and appeal of your house design. We provide disruptive energy to clients through innovative things that are even more appealing to them,” says Wanjiku.

The tiles are made of plastic and ceramic, and come in sizes, from eight watts to 150 watts, with the prices ranging from Sh2,000 to Sh25,000 per piece.

Each tile has two cable outlets that are used for connecting the power strings to the tiles to complete a parallel series power design.

Wanjiku says that most clients prefer the eight watts compared to the others because it identifies more with the typical household tile.

Initially, the company produced the tiles at a plant in Baba Dogo in Nairobi, but quality and quantity was compromised, and the cost of production was too high.

Patented Design

“We were not producing enough here and the production cost was too high so we went to China last year. The current three manufacturers we have partnered with give us the quality and quantity we need at reasonable costs. We have patented the design and the orders are done on need-basis and delivered to us in 45 to 60 days because of the shipping process. Plans are underway to set up our on assembling plant in Machakos County, a place where we can install the solar panels in the tiles ourselves and take control of the production process,” she says.

When installing the tiles, a household only needs a third of the rooftop installed with the solar tiles for it to have enough power to run on. Wanjiku says Kenya Power allows a residential household to run on 2.5 to 3kWh: “The solar cell efficiency of our solar tiles is at 70 per cent as compared to that of monocrystalline solar panels that range from 50 and 70 per cent. That means a full rooftop of Strauss solar tiles is capable of producing 9kWh, three times what the household requires.”

A third of the roof on the eight watts solar tiles exposed to five to six hours of the sun can produce to a maximum of 5kWh. The installation cost is Sh2 million for the tiles and accessories, minus the labour. The upfront cost of roofing with solar tiles may be 10 to 20 per cent higher than conventional roofing but in five to seven years, says Wanjiku, the client will recoup their investment. It is like buying shares and giving them time to earn you more.

After installing a third of the roof with Strauss solar tiles, a client can choose to complete the remaining two-thirds with Strauss plain tiles or choose another brand. Wanjiku says they have plain tiles retailing from Sh700 per piece.

“For consistency and uniformity, we advise our clients to consider finishing the roof with our blank tiles - blank to mean they have no solar panels. If the client is not willing, they are at liberty to try other brands,” says Wanjiku.

Wanjiku also points out that they like being involved in the project straight from design stage, if possible.

“We like to advise our clients on various issues one of them being the orientation of a building. A North-South orientation is better as compared to a East-West one.

This is because the former exposes the entire roof to sunlight throughout the day, hence ensuring maximum production, unlike the latter that has one side of the roof exposed to the sun in the morning and the other side in the afternoon hours. We also advise on the design of the roof to adopt. A gable roof is much preferred to a hipped one. The gable one involves less joints for the tiles and has minimal wastage as compared to the hipped roof,” says Wanjiku.

Pilot Project

Strauss Energy’s pilot solar tiles project involved installing a 2.5kWh solar system at Gaitheri Secondary School in Murang’a County.

The project, achieved through a grant from the United States Development Fund, was aimed at producing enough reliable energy to power a computer lab.

They are using this as an added advantage to seek out the government to try out their power in Kenya’s rural schools.

“We are grateful to Strauss Energy for providing us with reliable energy at no cost. When the whole of Kenya experienced a blackout in August this year, we at Gaitheri Secondary School never noticed. The solar power we have comfortably serves the entire school,” says an elated Lawrence Gaitho, the headteacher of Gaitheri Secondary School.

The company has partnered with a real estate developer in a mega project in Kitengela. The project involves full roofing of close to 700 houses in a gated community to achieve a one megabyte solar power system.

Strauss has ways of storing the excess power with options of sending 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 Wanjiku, whose background is architecture and project management. She was voted among the Top40under40 women this year by the Business Daily.