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Should I take my house off the grid?

20th November 2015

By: Terry Mackenzie-hoy

  

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Martin Luther King Jr ended his famous ‘I Have a Dream’ speech thus: “ . . . we will be able to speed up that day when all of God’s children, black men and white men, Jews and Gentiles, Protestants and Catholics, will be able to join hands and sing in the words of the old Negro spiritual, ‘Free at last! Free at last! Thank God Almighty, we are free at last!’”

To me, this sums up much of the motivation which people have in going off the grid, supplying their own electricity. And it is not just the freedom from Eskom or the local municipality; it is the deep satisfaction of being self-sufficient – like eating a tomato that you have grown yourself. The green movement helps as well. If you are off grid, then you have amazing street credibility. You have crossed the line. In a small way, you are saving the world. You threw at least one starfish back. It is all very satisfying.

From a financial point of view, it is really a big bite. It will cost about R233 000 to install a solar power system for a medium-sized house and, every ten years, you will have to replace the battery. One can work out that, with an electricity account of about R2 000 every month, your whole system will be cash positive after five years or so, allowing for tariff increases.

However, in five years’ time, the battery replacement cost will also escalate and you will probably have to replace a few components. In general, the R233 000 will not allow you to have a geyser or heater, and these will have to be fuelled in a different way. The big payback comes after about ten years, when your income from not having to pay Eskom becomes quite hefty.

The question is if, in fact, in ten years’ time, you will have to be paying a bill of the same magnitude for the same number of units (kilowatt hours) as you do now. For example, I have a plate stove in my kitchen and we do not use it. It is very inefficient. So, we cook on induction cookers and use a microwave oven with a thermal oven and a thermo fan. We do not use a central geyser to supply all hot water requirements – apart from the bathroom, there is an undercounter unit which provides instant hot water.

Replacing the down lighters with light- emitting-diode (LED) lamps has been costly but worth it. The electricity account is much less than it was, despite cost increases. The question is if this trend will continue.

Ten years ago, induction cookers were available but were uncommon. LED lights were available but were not very bright. This has changed. The issue is, when you install the equipment to go off grid, if, in fact, it does pay for itself, given that the alternative would be for you to consume fewer kilowatt hours and make extra money that way.

Batteries are another issue. The lead-acid battery was a financial con trick perpetuated on the gullible public. Very inefficient, the lead acid could be manufactured and sold at great profit. The lithium-ion battery, which has a far greater charge/discharge efficiency and longer life than the lead-acid, was available in the present form in 1985. It was not pushed until cellphones had to become lighter.

However, if you had invested in off-grid alternatives five years ago, you could have made a good saving by waiting for the lithium-ion battery instead of installing ‘long-life’ lead-acid gel batteries.

Thus, I am sure that, one way or another, it can be proven that going off grid is a good step financially; personally, I think it is borderline. I think going off grid is an emotional step, not a financial one. Having said that, it is a fact that all my outdoor lighting is solar powered. It lights up at dusk and turns off at dawn. And when I come home at night, it greets me and says to me: “We are yours and we cost nothing to leave on all night.” Free at last.

Edited by Martin Zhuwakinyu
Creamer Media Senior Deputy Editor

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