How to get off the Eskom grid

By Alan Duggan Time of article published Nov 25, 2015

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This article was first published in the third-quarter 2015 edition of Personal Finance magazine.

Most people think of load shedding as an annoying, but limited period (two-and-a-half hours in the Western Cape, four to six hours in Gauteng … possibly eight hours in the municipalities that owe Eskom billions) during which they cannot watch television, cook a meal, see where they are going or generally take advantage of 21st century technology. But it goes a lot further than that: load shedding also compromises our safety (see “Safety and security”, below) and costs us a lot of money as we scrabble to protect ourselves from its more painful effects.

At the time of writing in May 2015, Eskom was awaiting feedback from the National Energy Regulator (Nersa) on its urgent application to increase the electricity tariff by 25.3 percent for the 2015/16 financial year. The reason, says the power utility, is that it needs to recover the huge (R32.9-billion) cost of open-cycle gas turbines, plus a further R19.9 billion for its Short-Term Power Purchase Programme. Nersa says it is considering the application, taking into account Eskom’s operational and financial challenges and the urgent need to stabilise South Africa’s electricity network to avoid a possible total blackout.

So where does this leave us? There are many options, some of them relying on common sense (cutting down your electricity usage wherever possible) and others requiring a substantial upfront investment – and here we could be talking anything from a few grand to hundreds of thousands – that will undoubtedly save a bomb in the long term.

Committing to this kind of money requires a big leap of faith, but consider the alternative: if Eskom indeed escalates its tariffs as expected and the trend continues, you could be looking at a monthly bill several times larger than your present one. If you run a household equipped with all the mod cons, this could equate to several thousand rands more than you’re paying now. Against that, extending your mortgage bond to finance a sustainable power installation may be a bargain. If you are cautious by nature, you might prefer to dip your toes in the water by going partly off the grid. However, if you’re thoroughly sick of disruptions and deeply resent your ever-increasing electricity bills, you’ll be among a relative handful of people looking to go off the grid permanently.

Determining the most appropriate load-shedding survival strategy for your household comes down to a mixture of price (how much you are willing to pay for energy independence), convenience (some systems are fully automated, others require constant monitoring), property size and location (some options are definitely not suited to urban areas), and other factors. You may be content to stay with Eskom, seeking only to reduce the impact of regular blackouts.

In essence, these are the options: an array of solar photovoltaic (PV) panels, roof- or mast-mounted wind turbines, a generator powered by petrol, diesel or LPG (liquid petroleum gas), battery packs of varying capacities, or a combination of these systems.

Hello, sunshine

Devotees of solar energy say this option makes more sense than ever because new technologies, economies of scale and other factors have reduced the price of PV panels to the point where it is affordable even to those with a modest income.

According to a series of useful blogs on the website of Netshield (www.netshieldsa.com), a Pretoria-based company that offers energy solutions on both a domestic and an industrial scale, if solar is your preferred route, you have various options, from grid-tied to grid-interactive (or hybrid) to fully stand-alone.

The simplest system consists of solar panels and a control unit that ties into the national power grid. It feeds power to your home from the solar panels and from the grid. This system does not have a battery to store energy; instead, all electricity generated by the solar panels is fed through a device called an inverter, which synchronises this feed with the mains, offsetting what you would normally consume from Eskom. It slows, stops or reverses your meter, depending on the time of day, the amount of electricity you are using and the size of the system. (This doesn’t apply to all meters, though, and definitely not to the prepaid variety.) Without battery storage, any excess electricity produced by the solar panels goes to waste.

Whereas this is a great way to lower your electricity bills, it will fluctuate with the seasons and switch off when Eskom does.

A battery system, which will ensure a more reliable supply, is one of the most costly and maintenance-intensive components of any renewable energy installation. If you can’t afford a full system, a small, relatively inexpensive battery pack will deliver a certain amount of power during a blackout to certain appliances, including lights and a TV set or computer, but excluding geysers and other energy-gobbling devices (see “Battery back-up”, below).

A hybrid, or grid-interactive, system improves the reliability of your power. It includes a battery bank – small or large, depending on your requirements – and may include another power source, such as a back-up generator. The advantages are fairly obvious: if there is too little sunlight to satisfy your demand, electricity will be available from another source (grid, battery or generator). It can support an entire home, or just the items that are considered the most essential during power failures. These systems are more expensive because they require a large battery reserve capacity and additional controls.

Typically, depending on the amount of battery reserve, a hybrid system costs at least 50 percent more than a batteryless grid-tied system. However, it is less expensive and could turn out to be a more reliable solution than a pure stand-alone system, which is disconnected entirely from the grid.

Regarding the quality of solar panels, Herbert Teubner, general manager at Sinetech Advanced Power Products, observed several years ago that manufacturers in Taiwan and China were dumping low-quality PV panels on the local market. The problem, he said, was that it wasn’t easy to distinguish between the good stuff – which could last for 25 years – and shoddy products, which might lose their power-generating capacity and expire within a year. His recommendation was to stick with suppliers that have been in the business for a good number of years.

Since then, however, the flow of products from the Far East has increased quite significantly and, in most cases it seems, their quality has improved to the point where respectable installers are quite happy to recommend them.

Before committing your cash, you need to ask yourself a few questions, including:

* Do you want to install a stand-alone system and be totally free of Eskom’s tentacles, or are you looking for a back-up system to provide power during load shedding or power failures?

* Are you looking for something basic to power lights and a cellphone charger in your remote weekend cottage, or a system with enough guts to power a fridge and TV with decoder?

Installing a solar system is not just a matter of putting up a few panels and adding a few batteries, warns Sinetech. “There are many other factors and complex calculations involved, such as wiring, connections, environmental conditions, positioning of the system, physical location of the site, and so on.”

In order to price a solar system, a supplier will need to know the following:

* Usage: the total number of kilowatt hours (kWh) you expect to use each day. A small household may use 15 to 20kWh, a medium-sized household 30 to 50kWh and a large household 50 to 150kWh.

* Peak kW: the maximum kilowatts you use when all your major appliances are switched on at the same time. You should add about 25 percent to cater for “inrush” current – that is, when a fridge, washing machine or pool-pump motor is switched on.

To establish your average daily energy consumption, check your electricity bills over the past 12 months, add up the kWh figures and divide by 365. This gives you an average figure that incorporates the difference between winter and summer consumption levels. The more accurate you are with your calculations, the more money you can save, so take the time to check the plate on the back of each appliance for its consumption in watts (see the table – link at the end of this article – or go to Eskom’s website, www.eskom.co.za, which has a useful calculator).

Sinetech notes that not all daytime hours deliver 100-percent sunshine levels. The most efficient sunlight hours are from 9.30am to about 3pm. Fortunately, South Africa experiences some of the highest levels of solar radiation in the world, averaging between 4.5 and 6.5kWh per square metre of PV cells per day. When calculating sunlight levels, take seasonal changes into consideration and remember that the angle of sunlight changes from summer to winter; that is, you get less power in winter.

When considering where to put your solar panels, it’s important to select a site that does not shade the panels at any time of the day. Even a branch on a deciduous tree can substantially reduce power output.

Solar panels produce DC (direct current), so you must decide on your preferred DC voltage and calculate the size and number of batteries you will need. Battery voltage is difficult to change after your system is built, so choose carefully at the start.

If you want a simple power system that produces no more than 200 watts, a 12-volt system will probably suffice. A device called an inverter turns the 12-volt DC into 220-volt AC (alternating current, used in households). The size of the battery bank will depend on the storage capacity you require, the maximum charge and discharge rates, and the minimum and maximum temperatures at which the batteries will be used.

If you think you’ll need more than 500 watts, and you almost certainly will, then consider a 24-volt set-up. A technical advantage is that wires carrying higher voltages can run longer distances. If the solar panels need to be more than 30 metres from the house for adequate sun exposure, choose 24 volts or, even better, 48 volts.

For starters, forget about saving money by installing a bank of old car or truck batteries; they are not designed for solar power applications and will undoubtedly let you down. It is important to use deep-cycle batteries, so called because they are designed to be discharged repeatedly by as much as 50 percent of their capacity.

Even though they are designed to withstand deep cycling, these batteries will have a longer life if their cycles are shallower (that is, no more than a 20- to 30-percent discharge, which would require you to monitor their remaining charge and adjust the household’s consumption accordingly). The batteries have a lifespan of about three to five years, although more expensive 10-year versions are also available. Their lifespan is affected by environmental conditions, including temperature, so they should be stored under shelter, protected from the rain and kept as cool as possible.

Deep-cycle batteries come in a variety of types and capacities, including sealed lead-acid (which never need topping up), sealed lead-calcium, sealed gel cell, two-volt open-vented lead-acid (also called tubular) and lead-crystal. In fact, the choice can be bewildering, and novices are strongly urged to seek expert advice. For an example of types and pricing, visit www.sustainable.co.za

Blowing in the wind

Experts say a home wind turbine is “generally not recommended” if you live in a heavily populated area, because tall buildings and trees interrupt wind patterns and make wind power erratic. The turbines also risk annoying the neighbours, especially if they are mounted on towers.

However, you can reduce your energy bill and lower your carbon footprint by fitting a small wind turbine to your roof, possibly shaving as much as 10 percent from your monthly account. Alternatively, you could opt for an elevated wind turbine that sits on top of a tower, where it’s better placed to take advantage of prevailing winds.

Residential wind turbines are best used as a supplement to conventional power, says online merchant Sustainable.co.za, but they can also be used to fully power your home, provided that the blades span at least five metres and you live in an area with optimal wind conditions.

“Wind speed needs to reach at least 16km/h to generate electricity, and the more space wind turbines have to operate in, the better they work. For optimal residential use, an acre of space is recommended, but if you only want to supplement your current energy use, you can easily install a wind turbine in a smaller space.”

Wind turbines are divided into vertical- and horizontal-axis machines. Horizontal-axis turbines need to face into the wind to operate, whereas vertical-axis turbines aren’t dependent on wind direction. Another advantage of vertical-axis turbines is that the generator and gearbox are located close to the ground, making for easy maintenance and less stress on the tower.

Wind turbines can significantly reduce your carbon footprint, Sustainable.co.za says. In addition, excess power generated on particularly windy days can be stored in a battery or fed back into the national grid and used to credit your electricity bill, depending on your local authority’s by-laws.

Most of the disadvantages associated with wind turbines – noise, the interruption of TV reception, hazards to birds, bats and insects – have been disproved, the company claims, adding: “In fact, many studies that set out to prove the ill-effects of wind turbines end up proving the positive impact that wind turbines have on power consumption and the surrounding environment.”

Kestrel Renewable Energy, a supplier of wind turbines, says that, in its opinion, the best solution to the renewable energy challenge is a combination of wind turbine (to power a battery bank for lighting, computers and other low-drainage appliances), a solar water heater, and gas for stoves, heating and fridges.

A few things to consider when installing a wind turbine are:

* Your location. There should be no significant obstructions, such as trees or buildings.

* Installation normally requires permission from the local authority, so it’s important to explore potential planning issues before you proceed.

* An EIA (environmental impact assessment) is required when installing a turbine at a height of 15 metres or more.

Generators 101

If you intend to stick with Eskom, but want to protect your household from the annoyances of load shedding, you might consider investing in a generator – but do your homework first. Those hardware-store brochures carrying advertisements for generators may look tempting, but some are grossly inadequate for your domestic needs.

Specifically, if you want something that will allow you to run your TV, DStv decoder, phone charger and a couple of lights, you could pick up a suitable generator for a few grand. If you want generator back-up for your fridge, microwave, washing machine and toaster, be prepared to spend a lot more, and if you want to run all of these appliances at the same time, the required generator will definitely have to come from the Big League, with a price to match. Tumble dryer? Don’t even think about it.

As Eskom points out, generator under-sizing is one of the most common mistakes made by novices. If you underestimate your power consumption, you risk damaging the generator, as well as anything connected to it. If there’s any doubt, opt for a bigger unit. Oh, and unless you are an electrician, don’t be tempted to connect it to your home’s electrical system: a certified expert needs to fit an approved change-over switch and an overload protection circuit breaker on the main distribution board.

If you don’t want to install a change-over switch, a temporary extension lead from your generator can be used to plug in the equipment you require. It’s important that the cable from the generator is designed to carry the required load.

Among the considerations:

* The total electrical load to be used.

* Voltage, frequency and phase.

* Does the generator need to start automatically? If so, an automatic mains failure mechanism needs to be installed. If not, you need a procedure in place for manual start and switch-over.

* Suitable location for the generator: outside or in a ventilated area (your generator may not to be installed in an enclosed area, or indoors).

* Acceptable noise levels.

* Running time.

The ideal generator capacity depends on the sum of the electrical loads you want to power simultaneously, measured in watts, taking into account the maximum total load expected at any given time. First, add up all the loads you know you want to be able to run simultaneously. Then, as a precaution, figure out which electrical item in your house requires the most electricity to start its motor and add that to your total, bearing in mind that the start-up current of a pool-pump motor, for example, is about 1.4 times the running load, and the start-up current for large items, such as air conditioners and some refrigerators, can be two or three times what they use while running. Make sure your generator can accommodate the extra load so that larger items won’t overload the system when they start up.

Says Eskom: “Every generator has two wattage ratings: running wattage and surge wattage. Generators are rated for surge wattage, because they should have some excess capacity in case the load you need is temporarily larger than what you’ve calculated. When you buy a generator, choose the size based on the running wattage, and its surge wattage should automatically fall into line with what you need. If you’re worried about needing more surge wattage, buy a larger generator.”

In case you were wondering about it, no, you cannot simply plug your generator into a wall socket. This is known as back-feeding, Eskom says, and it’s very dangerous for a variety of reasons. “For instance, if someone forgets to throw the main circuit breaker to electrically isolate the house from the grid, the generator could send electrical power beyond the house and out on to the grid.”

Should the earth leakage or main switch be left on, Eskom says, the resumption of grid power could destroy your generator and could even cause electrical or other fires. “If you choose to switch off the earth leakage main switch to avoid this issue, you need to remember that your family is at high risk of electrocution when back-feeding power to your house, since the electrical system will not have earth leakage protection.”

You should never run a generator inside your house or garage, under a carport, inside a screened porch or near an open window. Why not the garage? Because even with the door open, carbon monoxide from the generator’s exhaust could build up to the point where it makes someone sick – or worse.

What can you do about the noise, and how can you avoid annoying your neighbours? This could pose something of a challenge: the more advanced generators do a better job than older ones at adjusting engine speed to their electrical output, reducing the noise and conserving fuel, but much depends on the electrical load you’re imposing on them. The only practical solution to the noise issue is to be sensitive to your neighbours’ rights and avoid running the generator at unreasonable times.

Battery back-up

Most individuals (as distinct from businesses) can cope reasonably well without electricity for a couple of hours, but for some, even 10 minutes without access to a TV or computer could spell serious trouble (in one household we know of, missing an episode in the final week of Australian Masterchef would probably trigger a parliamentary protest).

Do you work from home? You might consider installing a battery back-up system in the form of a power inverter, also known as a UPS (uninterruptible power supply). Charged from the mains and available in a variety of sizes, it converts DC from its built-in battery pack into 220-volt AC, allowing you to continue working (the length of time depends on the system and battery capacity) when the mains power is down, by plugging your device into the UPS. If you use a laptop, of course, its built-in battery eliminates the threat from power failures.

A UPS is not a cheap solution, though. Although most deep-cycle batteries will last for three years and more (assuming they have been looked after), replacing them will cost R1 000 and more, or double that if your system has two batteries. They are generally very reliable and come with two major advantages: they don’t disturb the neighbours and they are entirely maintenance-free.

One solution worth a look is the OmniPower Power Trolley from Sinetech, a fully portable, maintenance-free system that delivers enough power to keep your TV, decoder, desktop computer and other small appliances going while Eskom is juggling with the grid. Remember, however, that the back-up time is directly proportional to the load connected. For example, you could run a laptop with a load of about 80 watts for up to 10 hours, but if your connected appliances are drawing 800 watts, don’t expect to run them for more than an hour. The Power Trolley, with a starting price of R7 467, features a deep-cycle battery with a claimed lifespan of eight to 10 years.

Another compact system worth considering is the Tescom Apex Plus long-run UPS, featuring two high-capacity batteries. It can be connected to external batteries to provide continuous back-up power during a long-term outage. Expect to pay about R9 500 (from www.geewiz.co.za).

Electrical equipment retailer Ellies offers a neat standby system in the form of a steel cube on castors. Their 1 200W power inverter/UPS system comes with two deep-cycle batteries, overload protection and a built-in intelligent battery charger, and sells for R20 794.

If you like the idea of using sustainable energy to charge your portable power pack while the mains power is off, you might consider the neatly packaged Ecoboxx 1500, which comes with two 65-watt foldable PV panels, a battery, inverter, three USB charging ports and a variety of other useful features, including castors for easy transportation. Fully charged, it will run your 42-inch TV and DStv decoder for eight hours. Cost: a hair under R20 000.

If you’re thinking about something smaller to charge your cellphone and power a couple of low-energy lights during power outages, you can buy a small back-up battery unit from one of many online merchants or a chain store such as Makro or Builders Warehouse (when we last checked, however, they were running out of stock).

If the power goes out, you’ll still want to retain some means of communication, and if you use a cordless phone at home, it means losing your landline – so make sure your cellphone is charged. As a back-up, buy a small “power bank” (in essence, a compact rechargeable battery no larger than a cigarette pack) to recharge your smartphone or small tablet; you can find one for R300 and up.

Remember that your smartphone can also function as a portable wi-fi hotspot, allowing you to connect your laptop to the internet when your router is off. Be careful, though: a long session online, especially if it includes YouTube videos, will quickly eat up your data allocation.

SAFETY AND SECURITY

Our homes may be equipped with sophisticated security systems that include electric fences, CCTV cameras and other safeguards that may not be backed up by reliable batteries. And we rely on lights to illuminate our streets; take them away and you create a useful environment for criminals.

In similar vein, your security may be threatened when you get out of your car to open a non-functioning automated security gate. If the gate isn’t linked to an off-grid power source, the solution, such as solar back-up, could be quite costly. We found one solar kit that will operate a 12-volt DC gate motor, priced at R5 700.

If your alarm system doesn’t have battery back-up, a solar-powered solution will set you back about R4 400. And still on solar options, a stand-alone, wall-mounted light with motion detection will cost about R700.

The Security Association of South Africa said recently it was aware of instances in which criminals targeted businesses and households during load shedding, taking advantage of compromised security systems.

Aside from the threat to personal safety, there’s the matter of insurance. Some insurers are paying out for losses resulting from load shedding, whether it involves a criminal incident or an appliance “fried” by a power surge, but the costs are growing steadily and insurers will undoubtedly rethink their contracts.

One insurer reported a case in which a client was blow-drying her hair when the power went off. Without thinking, she put the dryer – still switched on – in her stocking drawer, and left the house. Later, when the power was restored, the dryer came on again and, within minutes, managed to ignite a spectacular fire.

WHAT DO YOU PAY?

Did you know that there is substantial variation in what you pay for electricity depending on where you live in South Africa, how much you use, and how much high users subsidise low users? For a medium-size household using between 1 000 and 2 000kWh a month, Cape Town’s prepaid rates are highest (R1.87 per kWh on units over 600kWh), with Eskom a close runner-up (R1.83). Durban (eThekwini) comes in lowest at R1.31. For a detailed breakdown, read “Domestic electricity prices of six metros and Eskom compared” by Chris Yelland on the ee Publishers website, www.ee.co.za

PIONEER IN HARNESSING THE SUN’S POWER

About eight years ago, retired medical specialist Anthony Keen and his wife, Rosemary, decided to explore the concept of generating their own power and becoming less dependent on Eskom. “At that stage, it was a research project, not a money-saving exercise,” Keen says. He accepted the cost of the research, but with the passage of the years, has decided his investment might be repaid after all.

Not that he needed convincing about the merits of solar energy. He had installed an all-copper solar water heating system in his home in Rondebosch, Cape Town, way back in 1984, paying R2 800 for everything, including a 350-litre hot-water cylinder (which still works like a bomb, he says).

“I wanted to see whether I could run a standard suburban house on solar energy without adopting the full hippie lifestyle and develop a strategy that would optimally integrate solar power, the Eskom grid and battery back-up.”

Before committing to any expensive equipment, this urban pioneer focused on reducing his household’s energy use, installing effective insulation in the roof and elsewhere, excluding draughts wherever possible, equipping the house with energy-efficient appliances, fitting energy-saving lights and generally optimising power consumption – for example, by cooking with gas (although he is now migrating back to solar electrical induction cooking), using a wood-burning stove to keep warm (he collects firewood from felled trees in the neighbourhood) and covering the pool in winter to avoid having to run the pump for months at a time (a black plastic sheet blocks sunlight, preventing the growth of algae). His efforts paid off brilliantly, reducing the household’s energy consumption by a remarkable 71 percent.

That accomplished, Keen fitted an array of 20 photovoltaic (PV) panels to the roof of his house (they have a nominal output of 3.8kW) and linked them to a bank of 24 deep-cycle lead-acid batteries, in turn paired with a sophisticated 6kW inverter. This device converts the direct current from the solar panels or battery to alternating current, manages the charging and discharging of the batteries (a critical function for their long-term health) and synchronises the system with the grid.

“The inverter has a built-in regulator that manages the power supply without you being aware of it.

It can draw on PV energy alone, take in electricity from Eskom, or use a combination of the two,” Keen says.

A wi-fi router sits atop the inverter, which occupies a corner of the lavatory, and feeds data to Keen’s laptop, where it is played out graphically to record the household’s energy usage.

As a back-up, he has a standby generator powered by a small three-cylinder Mitsubishi engine, powered by liquid petroleum gas, which delivers a nominal 10kW of direct current to recharge the batteries. It’s a neat and effective set-up, Keen says, but he hardly ever uses it.

Keen spent just over R262 000 on his domestic PV system to produce electricity at about R2.17 per kWh, averaged over the lifetime of the system (a nominal 25 years). However, this was over eight years ago, when PV panels were a lot more expensive and Eskom’s prices were downright reasonable. Back then, you paid about R48 per watt of PV panel; today you’ll pay around R12.

It was a long-term investment, Keen says. “The cost of my PV-generated electricity will still be R2.17 in 25 years’ time; where will Eskom’s price be after 25 years?”

As Keen sees it, relying entirely on solar power – that is, being 100 percent off the grid, with no battery storage – may not make sense for the average domestic user. He says: “Households use most electricity in the early morning and in the late afternoon and evening, when the sun isn’t performing too well. Batteries help to distribute solar energy to match demand.” Even so, he says, there will always be a surplus at certain times during the day.

“It is possible to reduce this by learning to live with the sun … that is, by shifting loads to sunshine time wherever possible and switching on appliances such as the dishwasher, washing machine, pool pump, borehole pump towards the middle of the day – in sequence, not together! But there will always be some surplus.”

According to Keen, regulations that make it illegal to send surplus power to the grid and be compensated for it make PV installations unattractive from a business perspective. “In South Africa, roof-top PV systems are not generally encouraged, so we struggle against logic, even though the country is desperately short of electricity. Eskom is terribly jealous of its monopoly. A feed-in tariff would help a lot,” he says.

A major stumbling block for wannabe off-grid households is the fact that municipalities derive “fat revenue” from the resale of electricity, Keen says. “It’s an integral part of their revenue stream, so it’s not in their financial interest – at least, not now – to encourage independence from the grid.”

Frustratingly, Keen says, his roof-top PV installation produces considerably more power on a clear summer’s day than he needs, but the local municipality isn’t interested in buying the surplus. In fact, they don’t even want it for free. This was one of the factors that prompted him to explore another element of sustainable energy – in the field of transport. The result: an apparently ordinary Fiat 500 parked behind his house that hides a secret. He has spent twice as much as the R107 000 he paid for the car having it converted to a fully electric vehicle with a range of 200km and an electronically limited top speed of 160km/h. It is “refuelled” via a wall socket that draws excess power from the household’s PV array and battery bank, and if those take strain, he can switch to Eskom power without a hiccup.

ESCAPE TO THE COUNTRY

British-born Nicola Vernon needs no persuading about the appeal of sustainable energy. Having relocated many years ago to a 40-hectare farm (“It was more like a field, actually”) near the small and friendly town of Greyton in the Western Cape, she and her ex-husband are living happily off the grid, running two houses and outbuildings on solar power. They use gas for cooking and remain gloriously untouched by load shedding and its related challenges. In fact, confides Vernon, she has learnt not be too smug in her Facebook updates, reasoning that her neighbours might become irritated if she keeps bragging about her lights staying on.

They were faced with a choice: either spend more than R150 000 to install Eskom power (at the rate of R40 000 a kilometre for the power line, plus step-up and step-down transformers) or go it alone and generate their own electricity. It wasn’t a difficult decision, recalls Vernon, and the experience has been thoroughly satisfying. The couple spent about R70 000 on the installation of a solar array, setting up the panels on the ground behind their houses and linking them to a bank of 12 deep-cycle batteries, with an inverter and charge controller to keep everything flowing smoothly.

They made a few mistakes, admits Vernon. “For starters, we invested R75 000 on a monstrous back-up diesel generator that we didn’t really need. Also, someone advised us to install truck batteries, but they were not at all suitable, so we ended up replacing them with deep-cycle batteries designed for forklift trucks. They were quite expensive, but should last for 20 years.

“If we remove the generator from the equation and recalculate costs in today’s terms, we would probably recoup our investment in three to four years.” Meanwhile, their well-insulated and energy-efficient straw-bale houses, equipped with wood-burning stoves and all the mod cons, keep them cool in summer and warm in winter.

Did they consider installing wind turbines as a back-up for days when the sun didn’t shine? Vernon is firm on this one: “We tried three, and all of them were rubbish, not to mention the noise they made. Solar panels, on the other hand, just sit there and quietly do their job.” (Evidence suggests that Vernon may have been unlucky with her choices of turbine. See “Blowing in the wind”, above.)

Aside from her work on the farm, which also functions as an animal sanctuary, Vernon chairs a community-based, non-profit organisation called Greyton Transition Town, which aims to inspire and empower the people of Greyton and neighbouring communities to achieve sustainability and resilience in the face of rising energy and food costs.

As an example of how money could be saved in the long term, Vernon cites the case of a local high school that pays a whopping R50 000 a month for its electricity. If the school were equipped with a R1.8-million solar-panel system, she says, the capital outlay (via a loan) could be recovered within about seven years – or even less if it generated enough electricity to run the meter backwards and it could sell the electricity back to Eskom.

Marshall Rinquest, the director of Greyton Transition Town, says he started exploring solar energy options when load shedding became annoying and the price of electricity began to rise. “I looked at various types and found that the cheapest system for my household – consisting of me, my wife and child – cost about R25 000. That was way beyond my means, so I did more homework and eventually found a little system for only R400. It provides just enough power to charge my phone or iPad and lets us see where we’re going after dark. When the Eskom power goes off, my house is the only one in the community with the lights on!”

Rinquest says he is spreading the word about the advantages of sustainable power, and hopes to upgrade soon to a system with panel, inverter and battery that delivers enough power for a sewing machine and a television. “It’s modest, but it’s a start.”

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