Rainharvest.co.za

Solar-Powered Desalination

admin — Fri, 10 Sep 2010 17:25:33 +0000

Saudi Arabia’s newest purification plant will use state-of-the-art solar technology.

Heat transfer: IBM’s concentrated photovoltaic system can focus 2,300 times the power of the sun onto a one-square-centimeter solar cell without causing heat damage, thanks to an indium-gallium liquid-metal alloy that conducts heat away from the cell. Credit: IBM

Saudi Arabia meets much of its drinking water needs by removing salt and other minerals from seawater. Now the country plans to use one of its most abundant resources to counter its fresh-water shortage: sunshine and solar energy. Saudi Arabia’s national research agency, King Abdulaziz City for Science and Technology (KACST), is building what will be the world’s largest solar-powered desalination plant in the city of Al-Khafji.

The plant will use a new kind of concentrated solar photovoltaic panel (PV) technology and new water-filtration technology, which KACST developed with IBM. When completed at the end of 2012, the plant will produce 30,000 cubic meters of desalinated water per day to meet the needs of 100,000 people.

KACST’s main goal is to reduce the cost of desalinating water. Half of the operating cost of a desalination plant currently comes from energy use, and most current plants run on fossil fuels. Depending on the price of fuel, producing a cubic meter now takes between 40 and 90 cents.

Reducing cost isn’t the only reason that people have dreamed of coupling renewable energy with desalination for decades, says Lisa Henthorne, a director at the International Desalination Association. “Anything we can do to lower this cost over time or reduce the greenhouse gas emissions associated with that power is a good thing,” Henthorne says. “This is truly a demonstration in order to work out the bugs, to see if the technologies can work well together.”

While the new concentrated PV solar panel technology might generate affordable electricity, solar power still costs more than fossil fuels in many parts of the world. But even with those high costs, using it to power desalination makes sense, Henthorne says. “You’re not doing it because it’s the cheaper thing to do right now, but it would be the cheapest thing down the road.”

Desalination plants typically use distillation. Most upcoming plants, including the one in Al-Khafji, will use a process called reverse osmosis, which forces seawater through a polymer membrane using pressure to filter out salt. Both these methods are energy-intensive. Saudi Arabia, the top desalinated water producer in the world, uses 1.5 million barrels of oil per day at its plants, according to Arab News.

The new plant’s concentrated PV and reverse-osmosis systems will use advanced materials developed by IBM for making computer chips.

In a concentrated PV solar panel system, lenses or mirrors focus sunlight on ultra-efficient solar cells that convert the light into electricity. The idea is to cut costs by using fewer semiconductor solar cell materials. But multiplying the sun’s power by hundreds of times creates a lot of heat. “If you don’t cool [the device], you end up overheating the circuits and killing them,” says Sharon Nunes, vice president of IBM Big Green Innovations. IBM’s solution is to use a highly conducting liquid metal–an indium gallium alloy–on the underside of silicon computer chips to ferry heat away. Using this liquid metal, the researchers have been able to concentrate 2,300 times the sun’s power onto a one-square-centimeter solar device. That is three times higher than what’s possible with current concentrator systems, says Nunes.

For desalination, IBM has worked with researchers at the University of Texas at Austin to develop a robust membrane that makes reverse osmosis more energy-efficient. Desalination is done today with polyamide membranes that get clogged with oil and organisms in seawater. The chlorine used to pretreat seawater also breaks down the membranes over time.

The new polymer membrane contains hexafluoro alcohols, a material IBM uses to pattern copper circuits on computer chips. At high pH, the fluorine groups become charged and protect the membrane from chlorine and clogging. As a result, water flows through it 25 to 50 percent faster than through currently used reverse-osmosis membranes, according to IBM.

The new membrane removes 99.5 percent of the salt in seawater. This is comparable with conventional polyamide membranes, says Menachem Elimelech, chair of chemical engineering at Yale University. “You need to achieve this high rejection, otherwise you can’t get good water quality by one pass, you have to desalinate again.”

The Al-Khafji desalination plant is the first of three steps in a solar energy program launched by KACST to reduce desalination costs. The second step will be a 300,000-cubic-meter facility, and the third phase will involve several more solar-power desalination plants at various locations.

Source: Technology Review

Many desalinization plants are not very environmentally friendly (heavy metal & industrial chemicals are often discharged) so any effort to reduce their impacts is a step in the right direction. Desalinization plants are notorious for their high energy consumption- this is the cause of much criticism from environmental groups. If Saudi Arabia can save the 1.5 million barrels of oil a day that it uses on desalination plants, the positive environmental benefits are obvious. Solar powered water purification plants would need an alternative energy supply at night; either fossil fuel based (non-peak electricity demands at night) or from another renewable energy source such as hydropower. Solar energy projects such as these will probably become miniaturized in the future for domestic solar powered water filtration systems. Solar power for homes is becoming more accessible to the public; solar energy is particularly suited to South Africa with its high irradiation rates (and especially the Lowveld- Nelspruit / Mbombela has one of the highest irradiation rates in South Africa!). Solar water heating is currently probably the easiest way to drastically reduce domestic electricity bills (by up to 50%!). Water Rhapsody Water Conservation Systems acquired the Yes Solar dealership because water and energy are so closely linked. Yes Solar markets and supplies a wide range of high quality Solsquare solar geysers (German-made, Eskom- & SABS-approved). Solsquare solar water heaters qualify for substantial Eskom renewable energy rebates and are installed by qualified solar installers.

Contact us for a FREE QUOTE on a solar geyser, water system (rainwater & grey water systems) or a JoJo water tank (we are authorised JoJo Tank dealers).

Water Tank Platforms: Guidelines

admin — Fri, 10 Sep 2010 10:37:22 +0000

The following tips/guidelines are provided to assist you or your installer. These tips must be read/used in conjunction with the JoJo Tanks Guarantee, which is available on all JoJo Tanks in the form of a sticker or in document format.

A robust base of at least 2 cm wider than the base of the tank (no polyethylene tank should “hang” over its base)

The base must be smooth; no sharp stones or hard objects should be in the concrete mixture on the surface (holes could be pushed through the water tank base when it is filled with water)

It is recommended that the concrete base be at least 150mm thick ( a 5 000 litre tank holds 5 tons of water!)

Any brick/concrete block type of product used to manufacture the base walls should be allowed to set/dry for at least 36-48 hours before pouring of the concrete slab

Rubble or sabunga used to fill in the constructed base must be properly stamped in, using the right tool/compactor/heavy stamper (human weight is insufficient to compact the rubble/sabunga)

The water tank base must be perfectly level (use a spirit level to check!)

Should lip-channel or beams be used, ensure that the material is treated with an approved product to prolong its life. The gaps between the lip-channel or beams should be no larger than 50mm (5 cm)

Source: JoJo Tanks dealer documents

Water tanks are often bought without much thought given to the very important base. A 10 000 litre water tank will exert 10 tons of pressure on its base! Similarly, water tank stands need to be built professionally to withstand the forces of a full water tank. Sturdy water tank stands can be built from brick and mortar; in this case the internal space can be used as a storage room or laundry room, etc. Serviceable tank stands can also be built from sturdy, treated poles (usually gum/eucalyptus poles in Mpumalanga and Limpopo). Steel water tank stands can be custom built to spec or ready-made kits can be purchased and bolted together. We highly recommend that any steel water tank stands are professionally built and are signed-off by an engineer (a 5 ton 10 ton tank full of water could cause extensive damage if the tank stand failed!). Water Rhapsody is an authorised JoJo Tank dealer so we can supply a full range of JoJo tanks and tank stands. JoJo water tank stands are available in the following heights: 1.5m, 3m, 4.5m, 6m & 9m for either 5000 litre water tanks or 10000 litre water tanks. All JoJo water tank stands are certified by engineers.

Water Rhapsody strives to offer a holistic range of sustainable solutions. Water scarcity and energy issues in South Africa are probably the two biggest factors affecting our daily lives. Our water conservation systems (see product demo) include rainwater harvesting systems, grey water recycling systems, greywater irrigation systems, swimming pool backwash recycling systems, water-saving toilet flush mechanisms and of course JoJo water tanks and rainwater tanks. Our acquisition of a Yes Solar dealership enables us to offer the best solar energy solutions on the South African market. Our current solar energy product line-up consists of Solsquare solar water heaters (German-made, SABS- and Eskom-approved). We work with Solsquare-accredited solar installers so that your solar geyser is professionally installed and qualifies for Eskom solar geyser rebates. Contact us for a FREE QUOTE on a water system, solar water heater or JoJo water tank.

Re: thinking water & energy

Build a Solar Food Dehydrator

admin — Thu, 09 Sep 2010 16:42:16 +0000

DIY Solar Dehydrator

Made from two cardboard boxes, some clear plastic wrap, and a little tape. You can build a nearly free solar dehydrator. Set it on a stool or chair and face it’s solar collector towards the sun, and you have a functional food preservation machine for little work and even less money.

The above picture almost says it all. Using a long thin cardboard box for the collector and a taller, nearly square, cardboard box for the drying box. Boxes could be made to size by cutting and taping together small cardboard pieces. Line the bottom of the collector box with a black plastic garbage bag or paint the bottom with black, water based, poster paint, (lamp black or soot mixed with a little vegetable oil would work as well). If you use spray paint or other toxic paints, let the collector bake in the sun for a day or two before use. Cover the top of the solar collector with clear plastic wrap or window glass, etc. Tape it together as shown.

To increase the efficiency, you may want to cover the sides and bottom of both boxes with fiberglass or styrofoam insulation.

Source: JR Whipple

A simple and effective way of dehydrating food with solar energy. Solar dryers would work well in South Africa with it’s high irradiation rates, particularly in the dry season when air humidity is lower. Solar energy is an under-utilized resource; we have so much of it and it’s free! Instead of using fossil fuel derived electricity, we need to shift to renewable energy resources if this planet is to have a future. Solar energy can be used for electricity production via photovoltaic solar panels and it can be used for solar heating. Solar water heating is becoming very attractive in South Africa as Eskom tariffs continue to rise (solar geysers can save a household as much as 50% of the electricity bill). Water Rhapsody water conservation systems (rainwater harvesting and greywater recycling) combined with Yes Solar solar solutions can help you live sustainably and save you money on your water and electricity bills. Contact us for a free quote on a water system, water tank (JOJO or Atlas water tanks) or solar water heater (made by Solsquare, Germany).

The Cri-Cri: The World’s Smallest Electric Plane Takes Flight

admin — Thu, 09 Sep 2010 10:14:48 +0000

Reminiscent of James Bond’s fold-away Acrostar mini-plane, the Cri-Cri is the world’s smallest electric plane and this week made its official maiden flight at Le Bourget airport near Paris. Jointly developed by EADS Innovation Works, Aero Composites Saintonge and the Green Cri-Cri Association, the lillipution aircraft is the first-ever four-engined all-electric aerobatic plane.

Designed with numerous innovative technologies, the Cri-Cri boasts a lightweight composite structure that reduces the weight of the entire plane, allowing for the additional weight of the necessary batteries and the four brushless electric motors and counter-rotating propellers. All this leads to zero CO2 emissions and less noise compared to thermal propulsion that also utilizes higher-energy density lithium batteries.

With the batteries, the Cri-Cri is able to maintain 30 minutes of autonomous cruise flight at 110km/h or an alternative 15 minutes of autonomous aerobatics at speeds reaching up to 250 km/h. For the test flight, the plane remained airborne for 7 minutes before landing.

“The Cri-Cri is a low-cost test bed for system integration of electrical technologies in support of projects like our hybrid propulsion concept for helicopters,” stated Jean Botti, EADS’s Chief Technical Officer. “We hope to get a lot of useful information out of this project.”

The Cri-Cri is not the only ‘environmental form of air travel’ that EADS is researching. Currently the company is also experimenting with algae based biofuel and a helicopter hybrid propulsion system combining electrical power with piston engines. With such technologies being enhanced, could it only be a matter of time before air travel is no longer one of the largest polluters on the planet, but one of the cleanest?

Source: Inhabitat

Green technology such as electric airplanes is developing at a rapid pace. Successful commercial production as opposed to wonderful once-off prototypes is often linked to whether the companies have oil corporations as major investors. The oil corporations obviously have a vested interest in maintaining fossil fuels as the primary fuel source. Have you noticed that the ‘green divisions’ of these oil companies often develop amazing alternative fuel technology (such as advanced solar powered machines) but the prototypes hardly ever go into production? If they do, the products are usually outrageously expensive. This is not a conspiracy theory! Some careful research reveals the truth! Hopefully the Cri-Cri electric plane remains independent of the oil corporations.

Water Rhapsody and Yes Solar have combined to enable individuals and businesses in water scarce South Africa to conserve and harvest water as well as to obtain free energy from the sun- solar energy. Our water systems are designed to conserve water without the need for much conscious input. Our greywater irrigation systems irrigate the garden automatically and our grey water toilet flush system uses gray water instead of perfectly good drinking water. The Grand Opus rainwater harvesting system is integrated into your existing water supply (water stored in rain water tanks) so that you are never without water. See our product demo for examples of our WWF Award-winning water systems. As authorised JoJo Water Tank dealers we can supply and install the full range of JoJo water tanks and water tank stands. Our Yes Solar solar energy division markets high quality Solsquare solar water heaters (German-made) that qualify for the Eskom solar geyser rebate programme. Contact us for a free quote on a water system, water tank or Solsquare solar geyser.

Integrated Rain Water Harvesting Project

admin — Wed, 08 Sep 2010 15:57:27 +0000

Green News: Integrated Rain Water Harvesting Project launched by Ecolink

Ecolink's Integrated Rain Water Harvesting Initiative

The Integrated Rain Water Harvesting Project (IRWHP) was formulated by Ecolink in response to a direct request for help from local community groups in the target communities, to address the need for local water resources development and management for food production and poverty reduction.

The overall goal of the project is to contribute to livelihood improvement for the rural community in the Ehlanzeni district of Mpumalanga province of South Africa.

IRWHP Pilot Project Areas

Ehlanzeni District Municipality:
Mbonisweni, Luphisi, Mjejane, Dwaleni

Ecolink is a non-profit is a non-profit organization that was established in 1985 by Dr. Sue Hart in response to a variety of needs within the former Ka Ngwane homeland. For over two decades, these rural communities have been receiving training from Ecolink staff in subsistence gardening, nutrition, and water management.

Source: Ecolink

Green, non-profit organisations such as Ecolink (based near White River, Mpumalanga) are an asset to our planet. Their humanitarian and environmental work sadly often goes unnoticed. Individuals such as the late Dr. Sue Hart are an inspiration to young learners. I was one of those young learners that visited Ecolink on school field trips from 1985 to 1989 and can proudly say that the holistic environmental principles that Dr. Hart taught had a lasting impression on me!

How to Finance a Home Solar Energy System

admin — Wed, 08 Sep 2010 13:27:53 +0000

When one looks at the initial cost of solar powering a home, many of us cringe at having to fork out to install the solar items that get us off grid either partially or completely.

A solar power system is an expensive home addition but it’s an extremely beneficial one, particularly given ESKOM’s price hike. If you don’t have thousands of rands to pay for these solar power systems up front, there are other ways in which you can pay for your home to be eco friendly…

One of the most obvious ways would be to apply for a loan for your residential solar power system. The problem with a loan is that the payments can be exorbitant and you could pay off a solar power system for years to come. A more economical alternative is to increase the bond on your home to include your solar system.

Getting finance for your solar power system might not be as difficult as you think. The most cost effective and economical way of financing solar power products like solar panels and solar geysers is to include it as part of your home bond. Bonds are long term loans and these loans can easily include your solar power products without increasing the monthly payment too much.

If you have a long term loan, one that will be paid off for the next 20 years or so, including your solar power system within your bond makes a lot of sense. In many cases, the monthly savings you will make from your solar power products will likely exceed the monthly bond payments for the system itself.

There are many benefits to using a solar power system in your home, and the payback is rewarding. solar panels and solar water heaters are only some of the solar power products available to install in your home. As electricity prices increase, so will your solar savings increase pro-rata.

Another great benefit that many of us overlook when installing a solar power system is that the solar system will increase the value of our home, especially in South Africa at a time when everyone is trying to find ways to avoid escalating electricity tariffs.

So, if you’re currently in the market for a new home, solar products such as a solar heater are that much more available to you through your bond. Certainly finances shouldn’t limit you from using a solar power system within your home.

Source: Urban Sprout

Yes Solar supplies high quality solar water heating systems made by Solsquare (Germany). Solsquare solar geysers are SABS-approved and qualify for substantial Eskom renewable energy rebates (Solsquare solar water heaters qualify for some of the highest Eskom rebates in South Africa!). Yes Solar works in close association with Solsquare-accredited and Eskom-approved solar installers so that your solar geyser is professionally and safely installed. At current Eskom tariffs, our solar water heaters typically amortize their cost within 36 months. As Eskom tariffs sky-rocket, our solar systems will pay for themselves over an even shorter period. When building a new home, inclusion of solar energy systems in the building costs amounts to a minimal percentage of the overall costs.

Through Water Rhapsody, we offer water tank installation, rainwater harvesting, grey water recycling and water-saving devices for swimming pools and toilet systems (see product demo). Our water systems can be retrofitted or built into new buildings and can be adapted to small households or large business blocks, lodges & hotels and hospitals. We are also authorized JoJo Water Tank dealers. Contact us for a free quote on a solar geyser, water tank or water conservation system.

SOLAR ENERGY: Solar Geyser FAQ

admin — Tue, 07 Sep 2010 09:41:13 +0000

Why should you look at solar heating in the first place?

Okay, so you aren’t that sure about it – here are the advantages of solar heating:

• South Africa has very high solar irradiation, so using solar power makes sense.

• Other than buying the technology, solar can save you money.

• Heating water with solar is free, so there is a reduction in monthly electricity bills.

• Less vulnerable to electricity price increases

• Financial rebates from the Eskom & the Government

• Using solar energy contributes to the environment:

• Using solar energy means less consumption of natural gas and coal

• By more people converting to renewable energies, less and smaller new power plants will be needed, thus reducing the potential damage done by these plants.

• Replacing your geyser with a solar water heater can annually save up to 3.5 tonnes of CO2 emissions and 6kg of sulphur dioxide, which contributes to acid rain.

What does a system consist of?

Solar water heaters consist of three parts:

· Storage Tank – this is where the hot water is kept.

· Collector – this is where the sun is used to make water hot.

· Booster – the booster is used to ensure that hot water is available during overcast days and at night.

Our system has an electrical booster, but a gas booster for off-grid applications is also available.

How does the system work?

Thermo siphon action occurs when the agent which is heated in the collectors expands, becoming lighter, allowing colder, heavier agent to fall to the bottom of the collector. The cold agent pushes the hotter, lighter agent back up into the storage tank, where the heat is indirectly transferred to the water held in the tank.

What is the difference between an indirect (closed) and direct (open) system?

With the indirect system, the liquid heated in the collector is NOT the household water, whereas with an open system, the household water flows through the collector. The two advantages of the closed or indirect system is firstly that the liquid can contain antifreeze, preventing the liquid from freezing in the collector and bursting pipes and secondly there is no lime scale build-up from impurities on the municipal water.

What prevents hail from harming the system?

The collector is covered by tempered glass, but should the glass break, it will merely reduce the efficiency of the system; you will not be with-out hot water!

What are the benefits of this system?

· Reduction of electricity bill

· Reduction of carbon imprint, which is good for the environment

· As the system is an indirect system, no chance of freezing and pipe damage

· None of the components are harmful to people, animals or the environment

· Tempered glass cover, which is hail resistant

· Adds value to your home

· Possible rebates from Eskom

What should be done when going away?

If you are going away for longer than a week, the element/electrical booster should be switched off, and ideally the collector covered.

Source: Solsquare

Solar water heating systems make sense in sunny South Africa. Although the initial cost of solar geysers seems high, the systems amortize the cost fairly quickly (usually within 36 months at current Eskom tariffs). In many countries where there are no rebates or subsidies, homeowners are still investing in solar geysers; why pay high electricity bills when you could use that money to pay off your own solar energy systems? Financing a solar geyser through your home bond is another option; solar geysers and solar panels increase the resale value of a home too. Water Rhapsody has acquired a Yes Solar dealership to enable us to offer the best solar water heating systems on the SA market: Solsquare. Solsquare solar products are German-engineered and are SABS- and Eskom approved. Contact us for a free quote on a solar system, water system (rainwater harvesting [FAQ], greywater recycling [FAQ], water-saving devices) or a JoJo Water Tank (we are authorised JoJo Tank dealers and supply the full range of JoJo water tanks and water tank stands).

Solar Water Heating – what, where, why?

admin — Mon, 06 Sep 2010 12:10:44 +0000

Solsquare use high quality Conergy tanks.

What is Solar Water Heating?

Solar hot water refers to the use of the sun’s energy to heat water for household and industrial use. Solar water heating systems generally consist of the following components:

A solar collector
A storage vessel
A heat exchange fluid in the case of indirect systems*
A pump in the case of an active system*

Southern Africa has an ideal climate for the use of solar water heaters and, given that the heating of water is the biggest single consumer of electricity for the average household and thus contributes to the bulk of the electricity bill (up to 50%), the installation of a solar water heating system can go a long way towards saving the homeowner money and alleviating the strain on the electricity supply in the region.

Traditionally, flat-plate solar collectors have consisted of a simple glass-topped, insulated box with a flat absorber made of metal and attached to copper pipes. The copper is painted black to maximise the amount of sun’s energy absorbed. Another type of collector is the evacuated tube collector consisting of metal pipes surrounded by glass cylinder that houses a vacuum. This type of collector is very efficient at capturing the sun’s energy. Both flat-plate and evacuated tube systems work well in South African conditions.

How to decide on a supplier?

You are strongly advised to install a system that is on the Eskom list [we supply Solsquare solar geysers; find the various Solsquare products on the list] of approved suppliers as well as being a SESSA Solar Water Heating Division member. Not only could you qualify for a rebate, but Eskom will check on the installation to ensure it has been done correctly. If you decide to buy a system that is not yet on the Eskom list (some suppliers are still in the process of testing at the SABS), you must look at the track record of the product, and talk to several owners of the system.

Besides cost savings, what are the other benefits of solar water heating?

In today’s beleaguered world, installing a SWH is simply the right thing to do. A domestic SWH with a two square metre collector could harvest up to 2,000 kWh (kilowatt hours) of energy from the sun every year. By displacing the Eskom electricity that would otherwise have been used to heat the water, 1,080 kg of coal and 2,800 litres of water are saved, while 1,956 kg of Carbon Dioxide, 320 kg of ash, 17.9 kg of Sulphur Dioxide and 8.4 kg of Nitrous Oxide are not discharged to add to the Planet’s growing burden of pollution. That’s an important gift to the Earth for any good citizen to consider!

Source: Sustainable Energy Society Southern Africa

Sustainable living revolves around to major factors: how we utilize our water resources and where we obtain our energy from. We have the solution to minimizing your carbon footprint and living sustainably: Water Rhapsody water conservation systems and Yes Solar solar solutions. Our WWF Award-winning water systems include rainwater harvesting systems, grey water recycling systems, water-saving toilet flush mechanisms, swimming pool backwash recycling and water tanks (see our product demo). Water Scarcity is a reality in South Africa; save water! Yes Solar supplies Eskom-approved Solsquare solar geysers that currently have one of the highest Eskom rebate ratings on the South African market. Contact us for a FREE QUOTE on a water system, solar geyser or JoJo water tank.

World Water Week focus on water quality progress

admin — Mon, 06 Sep 2010 10:12:44 +0000

Progress in efforts to improve water quality as a response to challenges facing the global water sector will be in the spotlight when delegates meet for this year’s World Water Week (WWW) in Sweden.

Water and Environmental Affairs Deputy Minister Rejoice Mabudafhasi will on Friday depart to Stockholm, where she will be representing South Africa.

The World Water Week, which will take place from 5 to 10 September, is a meeting of experts, practitioners, decision makers and leaders from around the globe to exchange ideas, foster new thinking and develop solutions. It is organised by Stockholm International Water Institute.

The discussions at this year’s event are expected to cover various water and related issues with the purpose to increase awareness and stimulate action on human daily activities that impacts on the environment including water, land and air.

The 2010 WWW will be held under the theme “Water Quality Challenges- prevention, wise use and abatement”.

Mabudafhasi will be accompanied by the 2010 South African Youth Water Prize winners, Nomfundo Zondi and Mduduzi Dlamini, learners from MehlokaZulu High School in KwaZulu Natal, who will be competing with learners from 31 countries in the Stockholm Junior Water Prize.

The South African Youth Water Prize commences at provincial and then national level where the national winner is selected.

Through South African Youth Water Prizes, the department encourages high school learners to identify water and sanitation related problems, conduct research and come up with innovative solutions to the identified problems.

An adjudication panel composed of representatives from the water sector and tertiary institutions guided by the criteria set by the international adjudication panel from Sweden is established to evaluate proposals developed by the learners.

The two learners’ research project titled “Solar powered Waste Management System” started from the desire to address a problem of high water bills and electricity bills incurred by their school, when water supply was suspended for a period of three weeks due to mismanagement of water.

The project is about filtration of water using sterilization and pasteurization of water and also promoting re-use of water and addresses various environmental issues.

Source: Simply Green

It is great that schools in South Africa are raising awareness about water. Education and knowledge is key to conserving water- probably our most precious resource in water scarce South Africa. Closely linked is energy (see Water and Energy – the Link); using solar energy to power water purification and water treatment plants is an environmentally friendly initiative. Water Rhapsody and Yes Solar have combined to offer WWF Award-winning water conservation systems and Eskom-approved solar water heating systems (Solsquare solar water heaters, also SABS-approved). Contact us for a free quote for rainwater harvesting, greywater recycling, water-saving devices and solar geysers. We are also authorised JoJo Tank dealers and can supply the full range of JoJo water tanks and water tank stands.

Create a Natural Swimming Pool

admin — Sun, 05 Sep 2010 07:45:12 +0000

By creating a natural swimming pool, also known as a natural swimming pond, you are helping the environment in several ways: you’re saving energy and water, lessening chlorine pollution, and starting a micro-environment that helps shift the general environment toward a healthy direction.

How to build a natural pool

A natural pool is much like a conventional pool to swim in—the water is clear and warm enough to be comfortable, and there is no murky bottom. But because nature is used to build and maintain it rather than manufactured materials and chemicals, a balanced, self-contained, self-cleaning ecosystem is created that is based on pure water surrounded by plants and flowers like lilies and trumpet vines; you’ll be swimming with butterflies and hummingbirds. These are the general steps to building a natural pool:

Hollow a hole in the ground. You can make your pool any shape, and as shallow or as deep as you want, but the key is to make sure the sides slope so the natural walls you’re creating support the pool.
Seal the pool by applying a layer of bentonite clay. It works as a glue, bonding with the soil particles and preventing pool water from seeping into the ground. You can also use a less environmentally-sound but easier option, and line the pool with rubber or reinforced polyethylene, preferably in black to attract heat from the sun.
If you prefer more conventional pool construction, consider using Rastra block, a material made from cement and recycled foam plastic.
Cover the bottom of the pool with 4 to 5 inches of clean gravel.
Create a separate zone of plants close to the pool. This shallow area holds specific plants that purify the water by enriching the pool with oxygen, using friendly bacteria to convert contaminants into plant fiber, and taking nutrients away from algae so it won’t appear. These plants include marsh marigolds, water lilies, water primrose, cattails, and rushes. Rocks can be added to filter out particles. Water flows back and forth between this regeneration zone and the swimming area. The water is cleaned by the plants, and because the zone is so shallow, the water is also warmed there. Differences in the temperature between these two zones also keep the water circulating.
Have an electrician add a pump for further circulating water between the pool and the plant zone, as well as a skimmer and filter to keep the pool free of debris. You may also want to have an ultraviolet light added for further cleaning of the water.
Finish the edges by putting plants all around the perimeter of the pool to stabilize it. They’ll anchor the soil and keep it from eroding.

Creating a natural swimming pool helps you go green because…

It saves energy. Since the sun and water circulation heat a natural pool, and the pump and filter used are much simpler than in conventional pools, much less electricity is used overall.
It saves water. A natural pool doesn’t get drained at the end of every season as conventional pools usually do. It is only filled once.
You aren’t using the materials you’d use to build a conventional pool that contain chemicals, which use a lot of energy to produce and transport, such as fiberglass and steel.
Since the pool cleans itself, you won’t be using chlorine, thereby keeping chlorine pollution out of the air, water, and earth.
You are creating an entire little ecosystem with many benefits: plants absorb carbon dioxide, pure water supports a healthy environment, and a habitat is created for creatures like dragonflies, fireflies, and birds.

Additional benefits

There’s less maintenance. Once you get the pool going, it only needs to be checked out about once a year to keep plants pruned and filters efficient. There is no testing of water, and no chemicals to add. It is self-maintaining; for instance, the pool will naturally develop friends like frogs that keep bugs under control.
It’s less expensive. A natural pool can he constructed for as little as $2,000 if you do it yourself. Of course it can also cost much more, but you save money in the long term because of all the things you don’t have to buy to add to it over the years.
A natural pool is a scenic environment all year round. In the spring, wildflowers come up around it; in the winter, it ices over and becomes a skating pond; in the fall, duck families may visit.

The land razed to build a conventional pool drives out plants, grasses, birds, and all the other life that exists within a small ecosystem. Conventional pools use large amounts of energy and water, and their high concentration of chlorine contributes to chlorine pollution.
The amount of chlorine used in chemicals to clean pool water is very high; as much as 95 percent (household bleach has about 5 percent.) In the upper atmosphere, chlorine molecules from air pollution eat up ozone; in the lower atmosphere, they bond with carbon to form organochlorines, which include hazardous compounds like DDT, PCBs, chloroform, and dioxins. Dioxins are believed to be the most carcinogenic chemicals known to science.

Natural pools were developed in Europe to counteract this problem; they have been very popular there for a couple of decades. One of the biggest public natural pools, measuring 5,000 square meters, is near Leipzig, Germany. During high summer, more than a thousand people use the pool in a day; testing of the water has shown it to be of drinking quality.

By filling up your pool only once. as in a natural pool, you are saving an average of 20,000 gallons of water a year, or 200,000 gallons over 10 years. That means the average of almost 7,000 gallons of water it takes to top off a natural pond per season can be supplied for three years by the 20,000 gallons of water saved by not having to refill the pool in just one year. Saving water is saving energy–pumping, treating, and cleaning water in wastewater plants after it’s used accounts for approximately 50 percent of a city’s energy bill. By using the sun (solar energy) to heat a natural pool, and using a less consumptive system of filters and pumps, you are saving in energy roughly the equivalent of what it takes to power an average home for three months. By removing chlorine from your pool, you are taking an average of 500-700 gallons of chlorine per year out of the environment—from the air, water, and soil.

Source: Greenyour

See an earlier post “What is a Natural Swimming Pool?” for further explanation of how they work and specifically in South Africa. In most parts of South Africa we do not have to contend with pools freezing over in Winter but we may encounter excessive algal growth, especially in the warmer Mpumalanga and Limpopo Lowveld. If building your own natural swimming pool is daunting, there are people in South Africa like Dr Jerome Davis of Aqua Design who can build an eco pool for you. Summer is here and swimming pools in South Africa are in use again. If you do not want to build a natural swimming pool, consider following some water-saving tips for your pool this Summer. A big waster of swimming pool water is the backwashing process. The chlorinated backwash water is also highly toxic to the environment. The solution is to install the Water Rhapsody Poolside Tank (see demo/”>product demo). This system reuses the dirty backwash water by processing it and returning the cleaned water back to the pool within 24 hours. Contact us for a free quote on our Poolside Tank or any of our rainwater harvesting systems, grey water recycling systems, JoJo water tanks or solar water heaters (Yes Solar).