In 2012 Kenya’s energy regulatory commission issued a legal notice to landlords in the country requiring them to install solar water heaters on buildings.
The Solar Water Heating Regulations requires all existing buildings within the jurisdiction of local authorities with hot water requirements of a capacity exceeding 100 litres per day to install and use solar heating systems.
A 5 year window period was offered to landlord to give them time to comply with the new directive. The regulation was expected to be effective from May this year. However, ERC said it will give property owners six more months to enable them to secure financing and installations.
Kenya came up with the solar water heaters requirement in efforts to encourage the use of renewable sources and ease pressure on the national grid.
Heating water is very expensive as it requires a huge amount of energy. It is believed that 18% of domestic energy is used to heat water. In most homes and businesses this energy is generated from fossil fuels – gas and oil.
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But many people still heat their water using electricity which is the most expensive way to heat water.
In the case of solar thermal panels, the sun’s energy is used to heat water which is stored in a hot water tank and drawn on when required. Usually there is an immersion heater or additional boiler for back-up which can heat the water to the temperature you want in the winter or provide additional water in the summer.
It is usually a good idea to get a professional installer to view your house to check if your roof is suitable and also to check how efficient your panels will be. There may be too many trees or other types of shading around your house to provide a return on your investment.
Solar water heating can also be combined with solar PV panels if roof space allows. This means that some of the electricity generated from the solar PV panels can be used to top up the solar heated water to the temperature required. This combination of panels is the most efficient way of generating your energy requirements.
How solar water heaters work
Aside from cost and greenhouse gas emissions savings, the beauty of a solar hot water system is its relative simplicity and durability!
There are two types of collectors used in a solar hot water service:
- flat plate collectors (suitable where tank roof mounting is required)
- evacuated tubes (more efficient and great for frost prone areas)
Flat plate solar collectors
Flat plate collectors work on copper pipes running through a glass covered collector, often connected to a water storage tank on the roof. The sun heats the copperpipes and the resulting hot water is thermo-siphoned out of storage tank.
Evacuated tube solar collectors
Evacuated tubes use (as the name suggests) consist two glass tubes fused at the top and bottom. The space between the two tubes is evacuated to form a vacuum.
A copper pipe (called a heat pipe) running through the centre of the tube meets a common manifold that is then connected to a slow flow circulation pump that pumps water to a storage tank below, thus heating the water during the day. The hot water can be used at night or the next day due to the insulation of the tank.
The evacuation tube systems are superior as they can extract the heat out of the air on a humid day and don’t need direct sunlight. Due to the vacuum inside the glass tube, the total efficiency in all areas is higher and there’s better performance when the sun is not at an optimum angle – such as when it’s early in the morning or in the late afternoon.
Failure to comply
According to Kenya’s Solar Water Heating Regulations failure to comply with the law will attract a jail term or a fine or both.
“Any person who contravenes or fails to comply with any of these regulations commits an offence and shall on conviction be liable to a fine not exceeding 9,708 U.S. dollars or to imprisonment for a term not exceeding one year or both,”
In addition, all electric power distributors and suppliers shall not provide electricity supply to premises where a solar water heating system has not been installed.
ERC said that the law will help Kenyans reduce reliance on electricity produced by fossils fuels as they contribute to emission of greenhouse gases.
Government data indicate that Kenya has an installed electricity capacity of 2,325 megawatts as at December 2016.
ERC noted that the majority of Kenyans still rely on biomass and firewood for domestic cooking needs. “The deforestation is contributing to the climate change,” said the energy regulator.
Advantages of using solar water heaters include: households are able to cut on energy costs. Again, solar thermal panels take up less space than solar PV panels. Their efficiency means that approximately 80% radiation is turned into heat energy. They are cheaper to install than solar PV panels and they lower carbon footprint.
The new law in Kenya is expected to create jobs in the renewable sector due to increased demand for the installation of solar panels.
Another impact of solar water heaters is that there will be reduced usage of power from the 
mains thereby enabling the government to ensure that more people are connected to the national grid.
According to the regulations, those to be affected are commercial buildings such as hotels, lodges, clubs, restaurants, cafeterias, laundries, eating places and similar premises. Also to be under the radar are hospitals, health centres and clinics and similar medical facilities.
Others are institutions such as universities, colleges, boarding schools and similar facilities.