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Investors show huge interest in SA’s wind and solar programme

PRIVATE sector investment in renewable energy generation will reach R193bn following the announcement on Sunday of another 13 preferred bidders for wind and solar photovoltaic (PV) projects by Energy Minister Tina Joemat-Pettersson.

Renewable energy is regarded as the quickest way to add capacity to the grid, but, as it is weather-dependent, it cannot provide base-load capacity. SA’s renewable energy programme is the fastest growing in the world and has seen large investment flow into the country, while prices of energy production have fallen.

In order to accelerate the programme, Ms Joemat-Pettersson said in April that in addition to the 13 bids she selected in the fourth window, a further 13 projects that were good to go would be added at a later date. The addition means SA has commissioned 92 renewable projects with the potential to add 6,327MW of capacity to the grid.

As part of their bids, independent power producers are obliged to contribute to socioeconomic development in the relevant area, with R19.1bn committed in projects in the next 20 years.

Several large multinational and foreign national power utilities in partnership with local entities have shown a keen appetite for the programme, which has four rounds, with a fifth anticipated in the second quarter of this year. As technology improves and risk diminishes, prices of renewable energy in SA’s projects have been plummeting.

The Department of Energy’s deputy director-general Ompi Aphane said “there had been an overwhelming interest from local and foreign investors who offered excellent prices, which demonstrates confidence in public-private partnerships (PPPs) in the South African energy sector”.

The process works through a competitive bid system in which bidders strike a power purchase deal with the department on behalf of Eskom, which undertakes to buy the power they produce.

Since the first window bid in 2011, the solar photovoltaic energy price has dropped 76% and has fallen 55% for wind. Wind tariffs are now competitive with the predicted cost of producing coal-fired energy at Medupi and Kusile.

Mr Aphane said the country had the potential to become “a global player for alternative solutions that will ultimately unlock Africa’s potential”.

In her budget vote speech last month Ms Joemat-Pettersson also presented plans to expand the production of energy by other fuels. Most significant was the release of a request for data for gas-fired generation. She said the request would “guide the design of a gas-to-power procurement programme” with a combined 3,126MW allocation.

The Gas Utilisation Master Plan, which is a critical building block of establishing a natural gas sector, was “in the final stage of internal approval” and would be released for public comment within the next three months, she said.

The first request for coal-fired generation by independent power producers, which was announced last December and was due to close this month, would be extended for another two months “in order to ensure a successful procurement process with firm results”.

The minister said the procurement of 9,600MW of nuclear energy would begin next month. The process to choose “a strategic partner” would be complete by the end of the financial year.

Article Source: Business Day Live


New solar PV backup solution launched

Powermode, a Johannesburg-based power-provisioning specialist has launched a new addition to the Soltra range of solar photovoltaic (PV) energy generating solutions.

The high capacity Soltra GTB 10 000, which complements the successful Soltra GTB 3000 in the Powermode lineup, is a 10kVA capacity, utility grid-connected, hybrid solar PV power system targeted at small-to-medium-size enterprise and domestic markets.

“The Soltra GTB 10 000 is designed to help businesses and households cope with load-shedding and power outages, functioning as a back-up rather than a complementary power source in these eventualities. This sets it apart from conventional solar PV power systems,” says Jack Ward, Powermode MD.

He says the GTB 10 000 is aimed at larger-sized installations, where it is capable of dealing with bigger loads with a greater degree of backup battery autonomy. “It is also able to obviate the need for costly diesel generators in noise-conscious environments,” notes Ward, who adds that it’s ideal for rooftop installations.

The new unit features an integrated charge controller and inverter and can be operated in three modes: linked to the electricity grid (grid-tied); as grid-tied unit with battery backup (in a hybrid configuration); or as a stand-alone hybrid unit.

The GTB 10 000’s built-in electronic monitoring system facilitates the back-up, by automatically drawing current from storage batteries when the mains power fail. “Switchover time is a rapid 15 milliseconds,” says Ward, adding that this is designed to protect sensitive computer and other delicate equipment from power ‘brownouts’ and ‘spikes’ common to South Africa’s unpredictable electricity supply.

The computerised system is also able to automatically prioritise its power delivery channels; to back-up batteries to facilitate recharging during daytime, for example, or to appliances during user-definable peak periods. At other times the system will automatically juggle power sources between, solar, batteries and the grid to meet changing demands based on individual consumption dynamics.

“In addition, the unit is also able to feed power back into the utility grid – legislation permitting – slowing or even reversing consumption meters to significantly minimise costs to the consumer.”

Ward says the Soltra GTB 10 000 and its companion, the popular GTB 3000, represent a new-generation of cost-effective modular solar solutions requiring a comparatively low initial investment.

“The units can be expanded in terms of capacity to meet future demands. They can also be configured as three-phase solutions to meet commercial and industrial users’ requirements,” he explains.

With the escalating cost of utility power and the imminent arrival of ‘smart metering’ systems that will allow municipal authorities to bill for electricity consumption at much higher rates during peak periods in a process known as time-of-day-billing, Ward maintains that solar solutions will soon be on par with conventional power from the perspective of amortised installation and maintenance costs.

“This is particularly relevant as prices are expected to rise exponentially for power consumed during peak periods in the near future,” he adds.

Article source: Cape Business News 

Sizing your load shedding system correctly

The sudden uproar of solar and battery “experts” driven by the need to mitigate the risk and inconvenience of load shedding represents a risk to the unwitting consumer, with all the technical jargon flying over the heads of most, including the seller or installer. It’s not as simple as plugging everything together and incumbents will know there is a lot of consideration that needs to go into sizing a load shedding and solar solution for its application.

In lieu of what I have seen happening in the market with grossly undersized systems being proposed to the markets that will not deliver on what is promised purely based on the general lack of knowledge on the subject, I will give you some advice from my own experience in system sizing and important considerations. I will cover, battery sizing and operation, solar considerations and sizing, inverter selection and ideal operation.

A few basic principles that you need to know:

·         (Power = Voltage x Amperage) This equation is absolutely critical to understanding your need and what your system can provide you with. Power expressed in Watts, Voltage in Volts and Amperage in Amps.

·         (AC vs DC) Incidentally not the world famous band, but rather the type of current flow that we use in everyday applications. Alternative Current (AC) is what we receive from Eskom, meaning the current changes direction 50 times each second at 50Hz. When you plug an appliance into the wall you will be using 230 Volts of AC power. Direct Current (DC) as the name suggests, only flows in one direction and is what you get when using a battery or the type of current that your solar power will generate.

·         The inverter is the device that you use to convert DC current from your batteries and solar to the AC current that you require for your appliances. Bi-directional inverters conventionally have chargers or rectifiers built-in which allows you to charge your batteries and in turn converts AC from your Eskom supply to DC for charging those batteries.

·         Grid-tie inverters and MPPT’s are used in conjunction with solar PV panels, where the grid-tie inverter converts the DC current generated by the PV panels directly into AC current in line with the standard required by the Eskom power network, allowing you to provide excess power to the utility grid. The Grid-tie system however does not provide you with load shedding backup as it is required by law to shut down when there is a power failure for line operator safety reasons. It is also heavily regulated and consumers need to become acquainted with their local regulations. The MPPT or Maximum Power Point Tracker is a charge controller that will optimise the solar yield and charge your battery bank. It will not convert DC to AC and is functional only to use solar with battery backup. This system will provide you with both solar power and load shedding backup.


The proverbial Achillies heel of any system, the sizing of your battery backup is literally the make or break for a good return on investment. It all starts at the manufacturer that will test a battery and give the battery specification at 25°C operating temperature and at a given hourly rate or C-Rate. This is absolutely critical to sizing your battery. The most well know battery size in the South African market is the 105 Amp hour 12 volt deep cycle battery and this battery is mostly given at a 20-hour rate or C-20. This means this battery will deliver a TOTAL of 105 Amp hours over 20 hours or only 5.25 Amps per hour for 20 hours when you divide the 105 by the 20 hours it is given at. So in essence when you use the equation above you will get Power = 12 Volt x 5.25 Amps = 63 Watts or 0.063 Kilowatt per hour for 20 hours.

The problem is that we do not have 20-hour load shedding periods, but only 2 – 4 hours per load shedding, which means we will not be using the battery at its 20 hour rate, but rather its 2 – 4 hour rate. This rate is hardly given by the manufacturer, seller or installer, but is critical to correct sizing. The same 105Ah 12V battery will have a reduced capacity at higher discharge rates and depending on manufacturer, may be in the vicinity of only 75Ah at its 3-hour rate. This in turn means the total of 75Ah divided by its hourly rate of 3 hours gives us a discharge current of 25 Amps and this multiplied by the voltage of 12 Volts will give us 300 Watts per hour for the duration of 3 hours.

You can see that four of these batteries will then give you 1200 Watts or 1.2 Kilowatts per hour for 3 hours and eight of them will give you 2.4 Kilowatts per hour for 4 hours and so forth. I have seen plenty of sellers and installers offering consumers 4x105Ah batteries using the 20-hour rate and selling these solutions as a 3 Kilowatt load shedding backup which is far from the truth. If you draw 3 Kilowatts from 4 of these batteries you will simply kill them in a matter of a couple of months and they will not last your entire load shedding period.

This is not even all the considerations as you need to look at your operating temperature, charge and discharge rates and especially the Depth of Discharge (DOD) which in turn will all influence your battery life.

In the next part I will cover the solar aspect, but be aware of what you buy, there are plenty “fly-by-nights” that will not size your system correctly, give you a cheap solution and never be able to carry the warranty.

Article source: Fin24


Solar Powered Classrooms In Focus

Cape Town – The South African technology company Ambit’s solar powered classroom is poised to provide “off-grid” electricity and connectivity to rural classrooms and help teachers overcome the pitfalls of load shedding.

It not only harnesses the continent’s most abundant resource, the sun, but can also provide power for the rest of the school.

The so-called education delivered intelligently (EDI) classroom is a standard, modular container-sized, fully operational classroom and ICT hub in one. It is already used with great success at the TlamaTlama Primary School in Tembisa on the East Rand.

Visitors to the upcoming SABC Education African EduWeek in Johannesburg from July 1 to 2 will be able to see an example of the EDI solar powered classroom on the Ambit Technology stand on the expo floor.

Conquering the digital divide

“The EDI solar powered classrooms are designed to be used in rural, remote or even urban areas,” said Louise van Loggerenberg, director of Ambit.

“Standard systems seamlessly integrate with solar PV, wind turbines and a range of other renewable sources. The classroom is fully insulated and can be supplied with electric lighting, heating or cooling and internet connectivity.”

The project was launched in July 2013 and 32 solar classroom solutions will be delivered and implemented by the third quarter of 2015.

Article source: Fin24


Using Solar Pool Heating

Energy costs always seem to be on the rise. This is largely due to the fact that we are using more energy then is available. Eventually our current energy sources are going to be depleted. That is why so many people are looking into alternatives. They are trying out solar power.

Solar power may not yet be ideal for every situation, but one place it seems to be the perfect match is outside. Solar pool heat is a great example of a perfect way to use solar energy. It is ideal because yourpool is going to be exposed to the sun and you are going to use your pool during the sunniest times of the year.

Solar pool heating involves one of two methods. It can be either passive or active. Passive solar pool heating involves simple methods and equipment. Active solar pool heating involves a bit more complexity. As the names suggest a passive system simply draws in the suns energy, while an active system actively collects the suns energy.

Passive solar pool heating is usually done with a solar blanket or pool cover. The cover soaks up the suns heat and traps in inside the pool to warm up the water. The downside is the cover can only be used when the pool is not being used and if there is not adequate sunlight then there will not be as much heat which can lead to colder water temperatures on occasion. Passive solar pool covers are quite easy to install. They usually have some sort of reel system that allows you to cover and uncover the pool without a lot of hassle.

Active solar pool heating involves collecting, storing and moving the solar energy. A solar panel, a battery and storage unit are all parts of an active pool heating system. Active pool heating systems can be complex to install, but they are more reliable then passive pool heating systems. To install an active pool heating system you need to run cables, install the panels and connect everything to the pool.

Whichever heating system you select for your pool-whether it be active or passive-it will ultimately be much cheaper than a gas or battery operation, which will require the constant replacement of limited inputs. They are also easier to install and much safer. Above all, the solar energy is free. You can save a bundle on your energy bills by using a solar pool heating system over other systems.

The Importance of Insulation R Value

Home insulation is a vital component of the home that you should consider, particularly during house renovation. If the home is not properly insulated, rest assured that insulation will be the most effective method to reduce your electrical energy usage. It is a proven fact that an insulated home is much more energy efficient, as the air conditioning in your home can substantially be decreased. Other than saving energy, home insulation also makes your home more comfortable to live in and helps to muffle sound. Dust and pests may also have a difficult time to come in your own home via the insulated doorway and basement.

An important consideration in insulation is the insulation R number. The R number indicates the efficiency of insulation material. The higher the R value, the more successful the material will be in lowering electricity usage. If you are planning to add insulation to your home and discover that there are already existing insulation, all that is required is to add an additional layer of insulation on top of your existing level. The insulation R value for existing insulation can be estimated by multiplying the thickness with a fixed number, which is dependent on the type of materials.

There are many types of home insulation available for power saving purposes. Probably the most common kinds are clothes insulation, paper insulation and wool insulation. In South Africa, mostly it will only be the ceiling that requires insulation, although insulating windows with double glazing is also a good idea in some areas.

Although the cost of installing insulation might be high initially, the money saved through lesser electricity usage is quite substantial in the long run. The required insulation R factor is an important parameter that needs to be estimated during the set up process. All recognized insulation materials will indicate the R value on the packaging. In colder areas you would require a higher R value than in warmer regions to achieve the same result.

The Importance of Safety Whatever Ceiling Insulation Types You Choose

When you are in a quest to saving energy at your place, ceiling insulation is one of the best things you can do. Ceiling insulation will reduce your energy consumption which will result in lowering of your monthly heating or cooling costs. With proper insulation, you will be assured that you will be able to enjoy the kind of temperature you want your home to have, in just a short amount of time. This is because proper insulation would ensure that your heating or cooling system will be able to function at its best. You would also be increasing the value of your place just in case you are planning to sell it. With the kind of benefits you can derive from it though, you still need to understand its safety considerations. No matter what kind of ceiling insulation types you choose to install at your place, you have to take certain measures to ensure the safety of your house and your family.

People in certain parts of the world are getting more and more concerned with fires that are started by wrongly installed insulation. Though many manufacturers would claim that certain ceiling insulation types are fire resistant, it is only to a certain degree. Such materials that are suppose to resist fire, will eventually give in, under different circumstances.

With the many fire reports that have been broadcasts in the television, newspapers and through the internet that have been caused by ceiling insulation, most of them are due to these ceiling insulation types that are installed too close to certain devices and electrical equipment. Because of this, you should take note that there should be a minimum distance between the ceiling insulation and certain items at your home. For example, the ceiling insulation should be at least 50mm apart from standard household light bulbs or incandescent lamps. If you are using halogen lamps, it should be farther away, such as at least 200 mm around it.

In addition to the distance, it is also highly advised to properly choose the kind of material you would be using in installing your ceiling insulation. It is best that you choose the kind of ceiling insulation that receives a higher heat resistance rating. This way, you are increasing the safety of your home by observing proper distance, as well as buying the material that can provide you with utmost safety.

Another cause of fire due to ceiling insulation is the incorrect way of installing it. Therefore, if you are not absolutely sure of yourself in installing it, then the best way to go about it is hiring an expert to do it for you. One of the best ideas in doing this is to search for a reliable company at your town, which is known to provide excellent service in terms of installing different types of ceiling insulation.

If you have just move to a new place in which the previous owner already installed ceiling insulation, you should have a professional ceiling insulation installer have a look at it. This way, he will be able to see if there are certain adjustments or enhancements you need to have to increase the safety of your place. Whatever kind of ceiling insulation types that have been already installed at your place, it is always best to have it checked to be on the safe side.

Ceiling Insulation – Good Reasons and Examples

Having ceiling insulation is not a way of decorating or improving its aesthetics but an essential ingredient that hikes up the comfort levels in your home. It is essential to have the ceiling insulated to prevent heat dissipation in cold weather so as to keep the inside of the house warm and cozy.

It is a great way to save on fuel and electricity bills which shoot up during winter when you use the heating systems indiscriminately in a bid to stay warm. The resistance to heat dissipation that is provided by the insulating materials prevents the accumulated heat within the house from waning and seeping out through the ceiling.

Having an insulated ceiling helps keep the inside of your house warm in cold weather conditions and cool in the summer. The most obvious benefit is of course the cutting down on electricity bills and the energy saving that you would achieve by doing so. It would also mean that you contribute in a small measure towards alleviating the energy crisis and also help towards environmental protection. There are numerous ways of insulating your ceiling properly and deriving optimum benefits from it.

The hot air that is generated from the heating source in the house would tend to rise up to the ceiling trying to dissipate the heat through the roof material to cool itself off. Having a ceiling insulation prevents the air from losing its heat and keeps the temperature of the home’s interior intact. The warm air is prevented from dissipating its heat thereby maintaining the room temperature without over using the heating system.

Fiberglass batt insulation is a simple and easy way to insulate your ceiling and is easy to be done. You do not require the services of an insulating technician and can do it on your own. It is also the most effective type of insulation to prevent heat dissipation. But although effective, the method of ceiling insulation is not very cost effective. If you fancy yourself to be a bit of a handyman, you could do the installation by yourself. The only thing you need to take is to not close any vents and to install it tight enough so as to leave no gaps in between.

The residential foam insulation is a more expensive option for insulating the ceiling but is durable and long lasting and you can gain value for the money spent over a longer period of time by saving on your heating and electricity bills. The foam insulation spreads to any area that is susceptible to heat loss and covers it up. The application procedure is simple and you can do it using a spray. Foam would not be good for homes that are not ventilated enough as it collects the damp and cause the walls and the ceiling to mildew over time.

A lesser expensive option for insulating your ceiling is the fiberglass blown insulation which is also less effective and cannot be installed by you yourself but has to be done by professional installers.

This form is however less efficient but better results can be achieved by using a double layered ceiling insulation of this form. Though expensive it would work out cheaper than the batt system of insulation any day. The material used for insulating your ceiling could either be fiberglass, cellulose or Rockwool, all of which work pretty well.

Ceiling Insulation In Warm And Cold Climates

Choosing the very best good quality ceiling insulation is the most effective point that you possibly can do, regardless with the type of climate you live in. It plays a very essential part in any house, regardless of size, or warm or cold weather.

Thankfully, consumers are blessed with a wide array of choices regarding insulation. So they could be picky as to what they install. Its purpose would be to preserve the cold from coming into your home, and preserving the heat inside. To the other hand, it’s going to hold your house from becoming excessively warm inside the summer months. That means you is going to be saving cash all year round on all kinds of vitality consumption. It is going to reduce your heating bills in the winter and your air-conditioning bills inside the summer.

Without good-quality ceiling insulation, you will be paying a lot extra cash in heating and cooling charges. So, not only is it good for your own sake, it’s also fine for the environment as you will be consuming much less energy and creating a lesser amount of greenhouse gases.

You will need to inform yourself on the matter so that you can be a smart consumer. Know all about your subject and about each and every particular solution. Weigh out the pros and cons of each one particular, and calculate the cost. When some could need the know-how of an experienced installer, others may well really be established through the house owner.

It is imperative that the insulation be put in as the manufacturer suggests, and handled with care to avoid its integrity from being compromised. If its, you might not be getting all the benefits out of it.

Blown insulation is among the least expensive choices in insulating ceilings. Unfortunately, it is also much less successful than other solutions, and must be established by professionals. About the other hand, fiberglass insulation may be set up by yourself, and performs incredibly nicely. Thus, you’ll be getting a great top quality product that is certainly quite inexpensive, and you can install on your personal to save even a lot more income.

Protect Your House Thoroughly With Insulation Boards

Insulation is any material or substance that provides a high resistance to the flow of heat from one surface to another. The single idea or premise that insulation is based on comes from heat moving from a warm area to a cold area. In the warmer times, heat tries to enter the house and on the colder days, the heat tries to escape. With vagaries like these, the purpose of insulation is to regulate the temperature by reducing the pace of the process. One way for some effective insulation is the method of absorbed insulation. These use materials such as aluminum foil and polyethylene foam which can be helpful in preventing the accumulation of cold and hot air and reducing heat transfer.

There are other forms of regulating the temperature too, in the insulation field. These are called the insulation boards. There are three forms of foam board products under several manufacturers names. They include extruded polystyrene, expanded polystyrene and foil faced or polyisocyanates unfaced. These boards are explained in detail below:

Extruded Polystyrene Foam or XPS is popularly known as the pink board or the blue board in edge profiles and in different thicknesses. This board is one of the most widely used insulation boards in the residential construction industry. XPS has an R value (measure of thermal resistance) of 4.5 to 5.0 per inch thickness. It is reasonably priced, light and easy to use. The product can be used to insulate the outside of foundation walls and even under the slabs of concrete.

Expanded Polystyrene Foam or EPS is the least used, cheapest quality foam available in the construction industry. The product may have an R value of 3.6 to 4.0 inches thick. This type of insulation boards is very similar to the foam which is used for packing “peanuts” and is used in insulated concrete form also known as ICFs.

Polyisocyanurate also known as polysio, is usually observed in all kinds of commercial and more recently with residential building projects. It has an R value of 7.0 to 8.0 inch of thickness. It also has a foil faced. The foil makes it excellent for insulation boards when radiant heat is involved. It is also the most expensive board, amongst the three.

Although foam boards are much more expensive compared to other insulation materials, such as cellulose or iberglass, it is mostly used in places where space limitations are encountered. Another reason for preference is, it is three times thicker than most of the insulating materials and because it has high R values. Also with materials such as polystyrene sheets, give a more peaceful and subdued home since, it prevents the entry of unnecessary noise. The house can have a sobering effect and can drastically reduce the cost of electricity. There are a number of stores both on-line and off-line that one may visit for the precise boards for the perfect fit!

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