By Alfred Nyakinda
Solar power is growing in popularity in Kenya, but its use is commonly limited to lighting and powering of a few basic domestic appliances.
To enable the wider productive use of solar energy for commercial purposes, the Strathmore Energy Research Centre (SERC) is looking at new ways of utilising the technology.
Among these is using it to provide access to water, an area in which the centre is training people from different fields, while aiming to train those without technical backgrounds in the future on aspects such as the benefits and functioning of solar-powered water pumps.
“We try to make it as non-technical as possible, as well as targeting farmers, because oftentimes you find that a farmer maybe wants to install a solar water pumping system, but they don’t know how to go about it,” said Sarah Odera, acting Director, Strathmore Energy Research Centre
A toolbox has been developed called the Solar Water Pump Irrigation System, which has a connected Global Positioning System that can tell the average climate of an area, the type of soils that are there and use this to estimate the amount of water needed per day for a particular type of crop.
“Based on that you are able to size your pump. It tells you this is the size of pump that you need and this is how much it will cost, so if you’re going to get a loan at a certain interest rate, this is the payback period,” said Sarah, “This will empower farmers and enable them to make informed investments.”
Equipment is provided for practical demonstration at a borehole at the centre, where trainees are able to weigh the benefits of a submersible pump versus a surface pump, both powered by energy produced by the institution.
As it is part of the university’s electricity-generating infrastructure, the centre has 400 solar panels on its roof generating 100 kilowatts (kW) of electricity. 20 kW are set aside for the centre’s use in its research and training.
Through the use of inverters, the centre converts direct current (dc) produced by the panels to the alternating current (ac) used for transmission of electricity.
In conjunction with its backup system that includes batteries capable of storing 32 kilowatt hours, the centre can maintain a continuous power supply for its activities.
This enables tests to be conducted without interruption, like those being performed on solar cooling technology in anticipation of preparing a training course on the subject.
Solar cooling can be used for storing perishable produce in solar fridges or making ice which can then be used for transportation of produce according to Thomas Bundi, lead trainer at the centre.
However, not all the equipment undergoing testing is dependent on a stationary grid. In the field of solar-powered transportation, the centre is testing a new design of solar-powered tricycles.
These vehicles have a solar panel on top that acts as a roof while collecting energy that is stored in batteries for use in powering a motor that propels the tricycle.
Currently, they are capable of carrying the rider plus an additional load of 100 kg and give one the option of pedaling if the batteries run out of energy.
“On a full charge, on an average terrain, they can go 50 km. From the data sheet, it can go as fast as 50 km/h, but with the modifications and all the extra weight I’ve seen it do 30 km/h,” said Thomas.
“To give the bike more usability, you can go with the inverter in the house and plug in anything, like a television or a fridge, as long as you still have excess energy.” he added.
Tests are also being conducted in electricity generation and distribution at the centre which help in determining how solar power can be used most effectively so as to encourage more people to use the technology.
An example is the work being done on the Fuel Save system, a hybrid system that runs on both solar energy and a diesel generator. The amount of power drawn from the generator is reduced or increased automatically depending on cloud cover.
Furthermore, an arrangement between the Kenya Power and Lighting Company (KPLC) and the university is helping both parties better understand how solar technology can function together with electricity from the national grid.
Of the 600 kW generated by solar panels all over the campus, most of the energy is used by the university, with the excess being sent to the national grid at a cost of US$ 0.12 per kW paid to the university by KPLC.
Elsewhere, the centre is seeking to partner with the Kenya Bureau of Standards to help improve the quality control measures applied to solar devices so as to ensure energy efficiency and safety.
Due to the rapid expansion of the solar energy sector in Kenya, many substandard products are being introduced into the country which can be dangerous and, when they fail, cause users to lose faith in the technology
Among other things, the research centre tests whether the brightness of energy-saving bulbs meets the manufacturer’s claims, measures the light dispersal of bulbs to determine how many of them a given area requires and examines how solar panels and batteries function under different environmental conditions.
“Efficiency of panels reduces with increased heat. So you want to test how the panel will perform in a place like Turkana,” said Sarah, “People will assume that when it’s very hot, for example, there will be a lot of electricity generation, but actually the efficiency reduces. So sometimes they’re disappointed. We can test the panels and tell you what you should actually expect.”
In order to meet the goal of increasing the number of qualified professionals working in the installation and maintenance of solar equipment in the country, the centre provides training at different levels that enables one to get licensed by the Energy Regulatory Commission.
Training occurs over a period not exceeding two weeks, with at most 15 participants at a time to enable maximum engagement and provide an opportunity for hands-on experience.