Failure by the Zimbabwe Electricity Supply Authority (ZESA) to supply adequate electricity has pushed many residents to opt for gas as an alternative source of energy.
Massive load shedding in the recent months has seen many residents switching to gas instead of firewood and paraffin. Avondale resident Wendy Mutize says, “It’s faster to cook with gas and at the same time cheaper than using other alternative energy sources like firewood.” She also expressed happiness with the lower levels of pollution that gas emits.
Gas which like petroleum is a fossil fuel but gaseous in its state, is composed mainly of methane (CH4). Geologist Tawanda Furamera explains, “Gas is formed along with oil fields and coal beds as a result of anaerobic digestion of various kinds of dead matter that include plants and animals, under the earth’s surface. It is drilled the same way as oil.”
Gas burns with lower emissions than other fossil fuels. This is largely because of the fact that it has only one carbon, making it greener than the traditional alternatives. Furamera said, “For the same amount of heat, gas emits 30% less carbon dioxide than burning oil, and 45% less carbon dioxide than burning coal, thereby reducing the impact on air quality.” Due to the clean burning process, gas doesn’t produce ash after energy is released. This makes it a convenient and expeditious source of heating and generating electricity.
Gas can be used in the form of compressed natural gas (CNG), biogas or liquefied petroleum gas (LPG). LPG (mostly advertised as LP gas) is however the most popular gas in Harare, sold at many filling stations and even by informal traders on street corners around the city.
“Gas has a high heating value of 24,000 Btu per pound,” said Furamera. He said this is why it widely used as a primary source of heating whilst cooking.“Its high flammability however makes is extremely dangerous if handled carelessly,” he said.
Some residents still desist from using gas due to fear of risks of explosions. “I rather stick to my paraffin stove because with children in the house gas is not really safe,” said Braeside resident Jacob Masengauta. He said a small mistake when handling gas equipment may end up in a huge explosion. “My children love playing with fire crackers and in the event of a leak with no adult around this may turn into a huge disaster.” Energy expert Shelton Ndlovu said a substance (containing carbon monoxide) that has a strong odour is added to help detect a leak. This reduces the risks of gas explosion. He said, “The substance may be harmful and cause deaths if not carefully handled.”
Gas is cheap (less expensive than gasoline and paraffin) and therefore cost-effective. “People can also make gas (biogas) from their homes by building a bio-digester in which they can decompose their waste,” said Ndlovu. He said the equipment required when using gas for cooking and heating is 50% cheaper than that required for electric appliances for the same purposes.
However, some of the appliances and equipment being sold on the market especially imports from Asian countries may pose danger of explosions. Ndlovu said, “To be safe buy your appliances from accredited stores.”