What you really need to know before switching to solar power
Thomas Falkiner talked going off-grid with two local pioneers - one who opted to go the expensive route and the other for a more affordable option
So you want to go off the grid? Perhaps you're an eco-warrior inspired by Elon Musk and looking to make a difference. Or a survivalist banking on being the last one standing when modern society goes tits up in the not-too-distant future. Hell, maybe you're just sick and tired of load-shedding leaving you in the dark every other winter night.
No matter your motivation, you've realised that the time has come to pull the plug and invest in your own mini power station: a sustainable bastion of joules and amps and watts that will meet all your energy needs, whatever happens.
It's a wonderful idea on paper - but where on Earth do you begin? And what options exist to meet your needs?
In the complex game of farming power, there are three main players: solar, wind and micro-hydro. Unless you live next to a stream or river, the latter is not an option. Wind is great if you live at the coast or in a consistently blustery area. But if you don't, well, it's not going to do much. So what we're left with, then, is solar: a resource we have in abundance thanks to our warm, dry climate.
THE NO-EXPENSES-SPARED OPTION
The sun's rays pack up to 2,400kWh of light energy per square metre; a solar panel converts this to electrical energy. It's a simple enough principle, but in practice I'm sure it's far more complicated. Which is why I've just pulled into the driveway belonging to a chap named Greg Ball.
Ball, the director of Climatron Projects and MD of Airco, has a sizeable home juiced without any input from Eskom. In a sea of resource-sucking houses, his abode is an island of self-sufficiency. "I'm interested in technology," he says over an espresso. "And the fact that you can actually live free of oil companies and large power utilities."
He's a man who understands the art of engineering, and his place is an example of an off-the-grid installation done right. The pitch of the roof is sympathetic with the horizon, to ensure solar panels receive more sun more of the time. Then there's a temperature-controlled annexe in the corner of the garage that houses a vital component of any off-grid setup: the battery bank that stores all excess electricity generated by the panels.
"I'm currently running 36 locally produced lead acid batteries. They're much cheaper than going the lithium-ion route. You're looking at around R1,100 for one. And as long as you keep them at a steady temperature, between 20 to 25°C, they should actually give you a reasonable life - six to 10 years. Look, occasionally you'll have to replace one now and again, but that's par for the course."
Then you get the inverter, the third and final piece of this equipment puzzle, that converts and distributes the direct current (DC) stored in the batteries into the alternating current (AC) needed to feed your appliances and lights.
A solar set-up powers a lot. LED lights, televisions, PlayStations. fridges, washing machines, tumble dryers and heat pumps.
Everything in Ball's house runs off the sun - even his cars. He and his wife were among the first local buyers of the all-electric Nissan Leaf, which is charged at home. "The two of them cost less than one Land Cruiser and they save us R8,000 a month in fuel - that's what we were paying to run a Volvo and Toyota Prado. Neither of them has ever been to a petrol station unless it's to buy bread or milk. I even pump the tyres myself because I've got a compressor in the garage. So I'm totally self-sufficient when it comes to cars."
But what about road trips out of town, far from viable charging points? "Well then you just hire a 4x4, fully kitted and drive it to wherever you want to go." A clever approach, especially considering the savings on services, tyres and insurance. "If you combine your motoring in with the solar solution there's a very big case for it. But having said that, even if you charge a Leaf on normal mains power it'll still use two-fifths of bugger all - because to do 2,200km in a Leaf is like R250 to R260."
All well and good, but what happens when the clouds decide to gather for a day or two or three? With the sun trapped behind pesky layers of vapour, and no generator in Ball's house, surely he would have to switch back to the grid?
"Yes," he admits. "But it would take quite a serious 'perfect storm' to put us out of power because we have quite a big battery bank." Ball has calculated that, on average, his household operates on around 40kWh of power a day.
At any given time his batteries hold about 80kWh, which should provide a 48-hour window - possibly more if you implement a bit of internal 'load-shedding' (not charging both cars, for example). "Remember, cloud cover on its own doesn't mean you're not producing any power. You can have cloud cover and these things are still producing 50% power because there are still UV rays present. But thick cloud cover partnered with rain - think English weather - and you're down to 5% of your production capability. Then, yes, you will have to resort back to the grid."
You could get around this by supplementing your setup with either a petrol or diesel-powered generator. The downsides: a) they can be very noisy and b) burning fuel, they're not eco-friendly. A good generator is also expensive. But if you are considering solar at all, then best you start preparing to part with some serious money.
Ball is the first person to admit that solar power remains pretty much the preserve of the wealthy - for the time being, anyway. "For a family of four you can start talking at R180,000. Now, this won't take your pool off the grid but it's going to take your fridge, alarms, garage, gates, water heating, computers and TVs - all of that off the grid.
"Look, you could also build it up over time. You could put in an invertor and 10 batteries, which would act as an uninterrupted power supply when the power goes out. This scalable solution would cost about R80,000. Then when you are ready you can add in the panels and bolt in some extra batteries."
GOING OFF-GRID ON A BUDGET
High costs may scare away many potential sun farmers. But there's always an exception to the rule - and one South African has gone solar for a song.
Director and actor Warrick Grier owns a two-bedroom cottage in the Western Cape hamlet of Suurbraak. "The property I bought was just a piece of forest on a river, which lent itself completely to an experiment with being off the grid entirely," he says.
Unlike Ball's house, which still has a municipal electricity connection, something that's tricky to avoid in urban areas, Grier's is totally detached from the powers that be. "I had the option of getting the services provided by the local municipality but I rejected them. I felt I could do without them [Eskom] and I didn't want any real involvement with them on that front.
"A friend and I created a solar system consisting of six 600-watt panels, eight batteries and an inverter. I think I paid about R35,000 for it, which is really very good. If you nose around, shop around - and if it is a system like mine that is not connected to the grid - then it's actually very reasonable. And that is what we managed to put together, sourcing different things from different people, coming up with a package that came in at that price, which was really terrific."
Grier has never put it to the test, but he speculates that his battery bank is good for about three days of reserve energy. He uses super low-voltage lights and doesn't waste any power on heating water. "I use gas," he explains. "I put a 48kg bottle outside and that has lasted me nine months - in fact it's still going. One of these bottles will cost you about R800, so you're paying under R100 a month."
In a true stand of sovereignty, Grier's off-grid living uses wild water as well as wild sunshine. "I take water from the nearby waterfall that comes into my house directly through a pipe that I laid up the mountain."
But what about contamination?
"The water is very clean to start with. It's slightly brown, but I have a basic agriculture filter system before it hits the house. I use it for showering and washing up. And then the tank on the other side of house is white water, rainwater from the roof, that's got a more refined filter. That's more for drinking, although I get most of my drinking water from the nearby pass - spring water leaks out of the mountain so I just fill up 25-litre cans with that."
This way of life is something of a novelty, one that very nearly eclipses the hype of the new Tesla Powerwall, soon be unleashed on our shores.
THE TESLA POWERWALL: A GAME CHANGER WHEN IT COMES TO BEING GREEN?
Invented by Elon Musk, the Tesla Powerwall is a sleek, liquid-cooled, lithium-ion battery pack that can be bolted to your wall and hold 7kWh of backup power. Some have been quick to sing its praises as the mainstream saviour of sustainability. Others are not quite sold.
Says Ball: "I think Musk is a very clever guy. but the power storage he's talking about is very small for South Africans.
"I would still use lead acid batteries. I understand why they're using lithium-ion because it obviously cuts down on weight but then you don't have a weight issue in the domestic situation. Yes, in a car, like the Tesla Model S, it makes sense."
The Powerwall might not be that beneficial to a family of four, but it can meet the simpler needs of flat dwellers: a group of urbanites for whom the installation of solar panels and battery banks and bulky inverters is a pipe dream. During load-shedding or outages due to faults, the Powerwall's 7kWh capacity can keep your home essentials powered.
GOING OFF-GRID REQUIRES A CHANGE IN MINDSET
Even if you've got the capital to sink into a legitimate off-the-grid solar installation, your humble abode may simply not be suited to it. It may be facing south instead of north, or have a steeply raked roof, or be too close to tall trees or other shade-casting obstacles. All of these factors come into play.
A home optimised for solar should look very different to a 'normal" house - it would more closely resemble a small office building. "Green houses don't always appeal to a lot of people from a visual point of view," says Ball. "So if you want to go green, you need to change your perceptions."
Apart from having some capital in the bank, a rejigging of one's mindset is perhaps the most crucial thing needed when contemplating the shift to solar.
Going off-grid requires investing money in the short term in order to save money (and the planet) in the long term. The time it takes to recoup your investment will vary widely with consumption, but a rough range is between three and five years. And given that Eskom tariffs have risen six times faster than overall inflation since 2007 (by 300.7% as against 45.1%), with no sign of relief, it could be a very savvy financial decision.
But if you have some money, the chances are good that you'd rather spend it on other things - especially in a consumerist society such as ours. Given the choice, most well-to-do citizens would buy two Range Rover Sports over a Nissan Leaf or a BMW i3.
In South Africa, appearances are everything, and consumption, status and conformity continue to overshadow sustainability.
We desperately need to rearrange our priorities and accept that wealth, perhaps now more than ever, needs to be used responsibly.
Only when that happens will more of us, like Greg Ball and Warrick Grier, flip the switch.
THE PRICE OF SOLAR POWER
We unpack the costs of four unique home solar systems
NOTE: Quotes include cabling, mounting structures and earthing kits. All quotes supplied by Dako Power in Strijdom Park, Johannesburg.
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