Solar vs heat pump in Cape Town

HvRooyen

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Aug 14, 2006
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Long time user of evacuated tube solar, in the interior of the country. Now looking at retrofitting an existing resistive element geyser in Cape Town.

I would imagine solar water heating is pretty useless during the winter in CT, making a heat pump the better solution? Anyone with experience of either?

Also: Can anyone recommend an installer in Cape Town?
 

swakop_toe

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Sep 17, 2013
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Had vacuum tubes on the Karoo farm.
Boils in summer, freezes in winter.

Now, in Cape Town, got a heat exchanger.
It does what is has to, no issues in 18 months since new.
 

swakop_toe

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Sep 17, 2013
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The label say 50dB.
Real world effect, it's noisier for my neighbours than for me.

No idea what it cost. Bought it with the house.
 

Nod

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Jul 22, 2005
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I went with a gas geyser. I didn't want to rely on Eskom for warm water again.
It also makes it easier to move to a complete off-grid solution in future.
 

Gaz{M}

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Feb 9, 2005
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Try gas, they are quite affordable, and gas is much cheaper than electricity.

Heat pumps are basically air conditioners. At the coast, they will rust and fail. The pumps also don't last and are expensive to replace.
 

calypso

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Feb 10, 2009
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Couple guys on powerforum are actually getting rid of the water heating solutions and adding another 4 PV panels to supplement the array and power the old school geyser.
Makes sense as its just one thing to look after, no annual maintenance and longer life.
 

akescpt

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Aug 12, 2008
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I went with a gas geyser. I didn't want to rely on Eskom for warm water again.
It also makes it easier to move to a complete off-grid solution in future.
how big a gas geyser for a 4 person family?
 

Nod

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Jul 22, 2005
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how big a gas geyser for a 4 person family?
We have a 24l/min for a family of 3, which might be overkill.
It is all about how many taps you might have open at the same time.
We do have shower heads that limit flow to 10l/min, this helps.
 

Marsie27

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Jul 21, 2014
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Long time user of evacuated tube solar, in the interior of the country. Now looking at retrofitting an existing resistive element geyser in Cape Town.

I would imagine solar water heating is pretty useless during the winter in CT, making a heat pump the better solution? Anyone with experience of either?

Also: Can anyone recommend an installer in Cape Town?
We are in Claremont, Cape Town and had a evacuated tube (18 tubes) retrofit done in December 2009, zero hassles or maintenance needed since then, other than recently replacing the pressure regulating valve on the geyser. Yes, there are some days when we get little if any benefit from solar in winter, but there are many when we don't need any electrical input at all. Today, for example, was totally cloudy/rainy till about 2 hours ago, and our panel shows the water temp as 60 degrees right now. That's fine for us for tonight.
Our daily annual average for 2005-2009 is 15.634 kWh, 2010-2018 is 9.278 kWh. Daily averages for May-Aug for the same periods: 17.998 amd 11.374 kWh. The figures are a bit inflated relative to the rest of the year, as we always have an extra 4 people for a couple of weeks in June/July/Aug, and sometimes need more geyser input then, which is why I averaged the periods.
 
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