Right, now this may not seem the most logical place to start but since many people are grappling with spiralling electricity costs, fears of further load-shedding and a general do-gooderness and wanting to save the earth…it’s bound to be a popular topic.
It is a fact that houses built from scratch now need to have some kind of alternative geyser arrangement (not Eskom power in other words) and that glass needs to be, at least, coated with an insulating film. But that doesn’t answer the big questions about power consumption.
Your first big dilemma is what kind of geyser to put in – or replace. Your old-style, and possibly old, electric geyser is as bad as people say it is. It chews up massive energy, constantly heats itself up, usually to a temperature that’s too hot, and then promptly empties just when you need some extra hot water.
If you are planning on keeping your current geyser you’re going to want to – at the very least – do all of the following things:
- Wrap it in a geyser blanket – not an expensive thing to do and it does make a big difference to how long the geyser stays warm, and how long it takes to warm up. You can get this at any Builder’s Warehouse-type place.
- Put it on a timer – a very simple modification to your DB Board allows a timer unit, which costs a few hundred rand from a place like Manly’s Plumbing on Jan Smuts, to be installed. This can be set to run the geyser for a few hours a day and, in combination with a blanket, that can be enough for hot water whenever you need it. The unit I have allows me to set different time intervals and also configure it per day so that I can run it longer when I expect to need more water.
- Turn down the maximum temperature – if you’re always having to put on the cold water to temper the hot then why heat it to that temperature in the first place. The exception might be the kitchen sink where you may want to scald the living crap out of your plates and pots. But I’d suggest using a kettle for that and saving a lot of money for the other 23 hours a day.
There’s not much more you can do about electric geysers. There are better, more energy efficient models on the market but if you’re going to do a full replacement it’s worth considering something less fossil-fuel guzzling.
If this is where you’re headed, there are three options: solar, gas and heat pumps.
The darling of the eco set, solar geysers appear to work like magic. They consume no energy but deliver hot water whenever you need it with just the mystical power of the sun.
That’s the theory.
The reality is that solar has three drawbacks:
- Cost: solar geysers cost a lot of money to install – something like 5 times as much as a regular geyser and at least 3 times as much as gas (see below). That may not worry you but when you calculate the actual savings you will get monthly, you will discover that there is a considerably long break-even time ahead of you. In the long-term, yes, this is the best option. But we’re talking 5+ years at least.
- What if it’s not sunny?: one of the big misconceptions about solar in general is that it somehow stores energy when it’s not sunny. This is not true, unless you have batteries which add massively to the install costs. So that means on cloudy days (and at night) your geyser will not heat. Which may not be a problem if you have enough water to see you through. But when it isn’t using solar, guess what, it’s using normal electricity. In a place like Joburg it’s sunny a lot, so you’ll still save money, but every time you’re using normal electricity you’re eating away at that break-even date.
- Constant heating: like a normal geyser, a solar geyser heats all the time. Not a problem if you’re using the sun but depending on geyser size this does mean you need a sufficiently large solar array to heat it in reasonable time. And, as stated above, once the water runs out you have to wait for it to heat up again like a normal geyser.
I’ll talk more about solar energy in general later but the point here is: solar is a great choice, it’s eco-friendly and cheap over the long-term. But it’s not cheap upfront and the payback time is long. And all you need is one vicious hailstorm to smash your panels and your breakeven might move completely out of reach.
Ok so Option 2 is a heat pump. A heat pump is, essentially, an air conditioner in reverse. It takes in cold air and produces hot air. And that heats the water in the boiler.
It is a lot more efficient than a normal geyser (3-4 times) and therefore is a great way to save money compared with traditional geysers. It’s also cheaper than solar to install, doesn’t require big solar panels on your roof and works at night and on cold or rainy days. They can also be retrofitted to your existing geyser.
The big flaw with heat pumps are that they are still electrical devices – efficient, yes, but electrical. That means when there’s load-shedding your heat pump will not run. Which means no hot water for you.
In theory heat pumps can also be configured to do other stuff like underfloor heating and heating your pool – but on investigation you will discover that all this doesn’t come for free and ultimately the overall financial outlay for all this stuff is considerable.
Finally, these are imported devices by and large. That means with the rand at it’s current level you are buying a pretty expensive piece of equipment. And depending on your geyser size you need a fairly big heat pump.
All that being said, if you’re bullish about Eskom’s ability to supply you with reliable electricity, a heat pump is a good option and is certainly a major improvement on traditional geyser at a better cost than solar.
So, we come to the option we picked. There are two types of gas boilers: one that works like a normal geyser and heats the unit up to a required temperature at all times. The other heats the water on demand only. If you’ve stayed in rustic holiday accommodation you will be familiar with a version of these gas geysers which have a pilot light burning at all times which then fires into full action when you turn on a tap.
The modern version of this uses electricity to light the gas and then heats the water as it moves through the pipes as you need it. The beauty of this is that you are using incredibly little energy compared with any other heating method.
The electricity required to light the geyser is minimal and you can attach a UPS device (essentially a battery) which will light the unit if there is a power failure or load shedding.
Depending on the size needed this still costs a lot more than and old style geyser but is considerably cheaper than solar or a heat pump, runs in all weathers, uses practically no electricity and as long as you don’t run endless baths all day long, very little gas.
Installing gas, of course, is extra unless you’re on a gas line – and you have to buy the gas, have the large bottles replaced and so forth. But gas consumption really is minimal: we have been running our 2 gas geysers and gas stove almost every day for close on five months and we still haven’t used one of the large gas bottles up.
Of course gas has its own drawbacks: the price is volatile because unlike the sun it’s not free; and every winter there is a period where gas supposedly runs out. When Eskom’s power stations stop City Power uses gas as a backup in some instances and so in theory there could be a shortage. Personally I’ve never seen this happen but of course there is a risk if you think it might.
Apart from that the obvious sense that it makes to only heat water as you need it with a cheap energy source seems unbeatable to me – and we’re really happy with the solution.
We used Florad (www.florad.co.za) to supply the gas geyser, and High Speed Gas (www.highspeedgas.co.za) to install the gas bottles and connect it all up. I’d recommend both vendors – they’re knowledgeable and helpful and (thus far) the products supplied work as advertised.
Florad also do supply both solar and heat pumps so are good people to explain more thoroughly the relative benefits and costs.