The solar water geysers  programme was a good project

Thu, 16 Feb 2017 14:08:03 +0000

 BY Ronald Lwamba

 A carbon emission tax is an environmental tax on emissions of carbon dioxide, as the gas is considered to be a heat trapping ‘greenhouse gas’ and the purpose of a carbon tax is to protect the environment by penalising emissions of carbon dioxide, which causes global warming.

I am mindful that some people, especially Republicans in America, think that climate change is a hoax. Pope Francis has added his voice on climate change. The encyclical about climate change has aroused a lot of interest from the general public with some saying that let him stick to religion and leave science to scientist forgetting that he was a chemist before being ordained.

Former Florida Gov. Jeb Bush, a Catholic convert, said, “I don’t get economic policies from my bishops or my cardinals or my Pope. I think religion ought to be about making us better as people and less about things that end up getting into the political realm.” Donald Trump thinks that climate change is a hoax perpetrated by China although according to the latest CNN news clip he now claims to be an environmentalist.

But while more than 80% of Catholic Democrats say there is solid evidence that the Earth is warming, just half of Catholic Republicans agree. And less than a quarter of Catholic Republicans believe that global warming is a man-made or poses a very serious problem.

The solar water geyser programme is an ideal project that can be funded by the carbon tax and people can buy into it because they can readily see its benefits, At the moment nobody knows what it is used for, The carbon tax was introduced in 2006 and the ZRA had been collecting the tax only from border points when vehicles are imported into Zambia or on transit, but the authority was not following up the vehicles to pay the annual tax. The Government later decided that RTSA starts collecting the tax from all inland vehicles at the time motorists were renewing their road taxes.

I get concerned at the low percentage of access to electricity in Zambia at 48% in urban areas and a paltry 3% in rural areas, fifty two years after independence bringing the national average to only 23% and yet South Africa in about twenty two years of independence has managed to have  an access to electricity of 85.4%.

In 2012, the World Bank recorded that Ghana had an electrification rate of 64.1%, much better than Zambia’s, which showed a significant increase for Ghana, which despite its challenges in meeting demand, has managed to increase its energy access by 15%. It is interesting to note how Ghana has solved its energy challenges.

The West African country is a beneficiary of two 225MW floating power plants, provided by Turkish powership manufacturer, Karadeniz Holding through a five-year lease agreement. The power barges rely on heavy fuel and natural gas as a feedstock, and can feed directly into the grid once connected.

With climate change being a key factor to consider, these barges are able to operate using Liquefied Natural Gas (LNG) as a feedstock. LNG is the cleanest burning fossil fuel available, and according to studies by the US Environmental Protection Agency, natural gas emits 117,000 pounds per billion Btu of energy input compared to 208,000 for coal.

And so the idea of Zambia supplementing its electricity from a ship docked off the coast of Mozambique is not so outlandish after all. This is the price to pay for an economy that is growing like that of Ghana.

The reduction in demand (during peak times in particular) from the residential sector means that fewer power stations need to be planned for in the future. Eskom has recognized that solar water heaters will play a major role in its demand side management (DSM) programme.

“If there is magic on this planet,” wrote anthropologist and naturalist Loren Eiseley in 1957, “it is contained in water.” If Eiseley were still alive, he would surely applaud the fact that more and more people in today’s society are waking up to the importance of conserving our water supplies. Yet he would doubtlessly point out that the magic of water includes even more than its life-giving properties.

One of the reasons which makes water so essential to life is its ability to be a carrier for other things. It is called the “universal solvent” in scientific circles, because it can readily transport nutrients and wastes in, through and out of living systems. Water is also capable of holding and carrying heat. Our vast oceans of water absorb and hold the sun’s energy, regulating temperatures and weather on our planet.

This magical ability of water to retain heat can be used in the home, by installing a solar water geyser. A solar water heater or geyser is a solar energy system that uses the sun to heat domestic hot water. Just like a solar electric system, it uses panels or collectors to collect solar energy. However, these panels contain a water-based fluid that carries the sun’s heat down to a tank containing water. Without mixing the fluids, the system transfers the sun’s heat into hot water supply using a device called a heat exchanger. The cooled fluid returns to the panels to pick up more heat — and this results in an emission-free hot water that can be used to shower, do laundry and wash the dishes.

The use of a solar water heater does not result in reduced water consumption but it does carry with it many benefits. Here are just a few:

1. Fighting climate change.

Water heating accounts for 40 percent of a typical home’s energy use. That is many tonnes of carbon going into the atmosphere. Switching to solar hot water is a great way to reduce carbon and other greenhouse emissions to protect our climate. However, if the solar geyser replaces an electric geyser using hydro based electricity as is the case in Zambia until recently with the introduction of a 300MW coal-fired power station, there is no effect on carbon and other greenhouse emissions because both solar and hydro are renewable energy.

Avoidance of electricity demand by use of SWH, acronym for Solar Water Heater, results in increased hydro storage which is then available for peaking. SWH moves water heating into base load supply. But Zambia has now started generating 300MW using coal in its energy mix, there is, therefore, a reduction of 300/2600, 2600MW being the total installed generating capacity in Zambia. Climatic hazards caused by extreme weather events are a threat to biodiversity resources in the country. Droughts and floods in particular, adversely affect biodiversity resources in both terrestrial and aquatic ecosystems.  In recent years floods and droughts have caused crop failure, impacted on wildlife populations and changed the honey flow period.

It produces zero net emissions of greenhouse gases, enabling both industry and government to work towards meeting international agreements on the environment. Solar energy is renewable, abundant and a natural energy source. The rooftop of a house in Zambia would collect at least 20 times as much energy from solar as is required for water heating. The lifetime of solar heating technologies is usually greater than 20 years. Solar heating can be easily integrated into the existing water heating systems of buildings.

From a national perspective investment in solar water heating should be encouraged by Government and Government should spearhead its uptake for the following reasons:

• Job creation from growth of the

Solar Water Geyser sector

• Although the cost of a solar geyser is usually more than the cost of an electric system, today’s solar heating systems are cost competitive when the total energy costs over the entire life of the system is considered

.Carbon dioxide traps heat in our atmosphere, contributing to the greenhouse effect, which alters

our planet’s climate and ecological systems. Using solar energy in place of nonrenewable fuels may also reduce nitrous oxides and sulfur dioxides, which are components of smog, although Zambia is still far from having smog filled cities like New Delhi.

2. Protecting air quality.

300 MW is now coming from burning coal. Particulates and other byproducts of burning coal pollute our air and contribute to a number of negative environmental and health effects. Using a solar geyser becomes a part of the solution to these public health problems.

3. Protecting water quality.

Carbon and particulates aren’t the only byproducts of burning fossil fuel. Coal power plants are a primary source of mercury and other toxic heavy metals being released into the environment. These substances are a major threat to the health of rivers, streams and lakes — and to human health as well. Solar water heating is one practical step we can take to put a reduction to mercury contamination of our watersheds.

4. Monthly savings.

A solar water heater can provide up to 80 percent of a house’s hot water needs, even in temperate climates. This translates to major utility bill savings, month after month. In fact, a solar hot water system typically pays for itself in just four to eight years, and can be expected to last for 40 years or more. That’s a lot of free energy, and a lot of savings. The following table shows savings based on a 40% saving on electricity bills.

5. Increased home value.

Studies in other countries show that homes with solar geysers sell faster and at higher prices than those without. Thus, adding solar hot water to a home is an investment that will pay back whether the house is sold or not. Often, the entire initial cost of the system can be recovered when the property is sold. Depending on the type of conventional fuel used, replacing an electric water heater with a solar heater can offset the equivalent of 40% to 100% of the carbon dioxide emissions of a modern passenger car.

 DEFORESTATION

Zambia is regarded as one of the highly forested countries whose forests cover accounts for about 60% of the total land area estimated at 64 million hectares. However, Zambia’s deforestation rate is alarmingly high. According to recent data by the Centre for International Forestry Research (CIFOR), Zambia’s deforestation rate currently stands at between 250 to 300 thousand hectares of land per year. In fact, environmental experts have warned that Zambia’s forests risk becoming deserts in the next fifteen years going by the current rate of deforestation.

But why are people cutting trees indiscriminately? In Zambia, there are several reasons: clearing of land for agriculture is one factor, but logging for timber and cutting trees for firewood and charcoal burning rank top on the causes.

The Author has worked as a Town Engineer for the then Municipal Council of Livingstone and Zesco, initially as a Resident Engineer for Itezhitezhi rising to the post of Senior Manager, Civil Engineering where, among other things, he was in charge of the preparation of feasibility studies for hydropower projects. He holds a Bachelor of Engineering Degree (Civil) from the University of Zambia (1974), Post Graduate Diplomas in Water Resources Development (University of Roorkee, India) and Hydropower Development (University of Trondheim, Norway) and a Master of Engineering in Water Resources Development (University of Roorkee, India).