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ozwinner
23rd August 2003, 07:44 PM
Hi all
I had a solar hot water system installed about two weeks ago.
If you are thinking about doing it................. well do it.
I should have done it years ago ( but the cost stopped me).
I'm not a greany, but I like to do what I can, I can see the benefits already.
The system cost $3500 installed, thats after the gov' rebate of $1500.
I went up on the roof, the day after it was put in, and felt the outlet pipe from the collectors, you couldn't hold your hand on it for too long.
We live in Melbourne, its winter, 13 degres c, I'd hate put my hand on the outlet pipe in summer!!!!!!!!!!!!!!!!:eek:
They say that 80% of your elictricity bill is for hot water, and you can save 80% of that, with a solar hot water system.
Cheers, Allan:)

Sturdee
24th August 2003, 05:44 PM
Whilst I agree that solar hot water is good for the environment I don't agree with your electricity cost savings.

Three years ago when I replaced my HWS I looked into solar and found that electric was much cheaper in capital cost and preferable because of low running cost.

I have an electric mains pressure HWS running on night tariff and last year the annual cost of hot water was $ 152. If solar saves me 80 % it would ( without taking into account foregone interest income of the higher capital cost) take 28 years for it to have paid for compared with 5 years for my existing one.

Incidently only 6 % ( yes six ) of our electricity bill is for hot water.

Regards,


Peter

Daniel
26th August 2003, 10:26 AM
Just word of advice for anyone thinking of putting in a boosted solar hot water service.

It is best that you have control over the boost system, get the installers to put a switch in the kitchen which allows you to control the thermostat.

What happens a lot of the time the tank is hot enough to supply adequate water at a suitable tempreture to the house but the booster senses that it is not at the tempreture set and goes through the boost process and thats where you use heaps of energy.

This method requires a bit of planning with electric boosted systems because of the off peak power rate.

Just a bit of advice.


Daniel

journeyman Mick
29th August 2003, 11:04 PM
Of course it all depends on where you live, last place we lived in for 5 years and we turned the booster on for a total of 24 days. There's definite advantages to living closer to the sun!:D

Mick

soundman
30th August 2003, 11:11 PM
IMHO hot water is a subject that there is a large amount of unreliable information (read misinformation) going round.

It pays to do your sums before you believe any propaganda.

My summary.

Solar hot water is a good idea but it is currently a much more expensive option.

The government wants to minimise electrical demand any way possible so they dont have to fund more power supply. Even if it costs you more.

The power authorities want you on off peak tarif so that they can load shed your hot water at any time they like.

The savings on electricity provided by all these methods in not significant in most households. Most house holds total hot water cost is less than the cost or a mars bar a day.

Cost savings from solar hot water and energy saving globes are grosely over estimated.

Subversive comment ends.!!!

Cheers

Richard Crago
18th March 2008, 05:22 PM
Whilst I agree that solar hot water is good for the environment I don't agree with your electricity cost savings.

Three years ago when I replaced my HWS I looked into solar and found that electric was much cheaper in capital cost and preferable because of low running cost.

I have an electric mains pressure HWS running on night tariff and last year the annual cost of hot water was $ 152. If solar saves me 80 % it would ( without taking into account foregone interest income of the higher capital cost) take 28 years for it to have paid for compared with 5 years for my existing one.

Incidently only 6 % ( yes six ) of our electricity bill is for hot water.

Regards,


Peter
Yes it's the capital cost that hurts. In my previous house in Wagga, with off peak electric booster, my flat solar HW panels worked v well (with anti frost valve); OP electric cost was around $50 per year for wife and self (no dishwasher). Overall about 30 - 40% of KWhours was for above.
Guess you would have lots of electric appliances? Cheers Ric

Richard Crago
18th March 2008, 05:33 PM
Just word of advice for anyone thinking of putting in a boosted solar hot water service.

It is best that you have control over the boost system, get the installers to put a switch in the kitchen which allows you to control the thermostat.

What happens a lot of the time the tank is hot enough to supply adequate water at a suitable tempreture to the house but the booster senses that it is not at the tempreture set and goes through the boost process and thats where you use heaps of energy.

This method requires a bit of planning with electric boosted systems because of the off peak power rate.

Just a bit of advice.


Daniel
In our new house with endless solar system, + instant gas booster, we had to pester and pester plumber to put a separate line in for kitchen, where water is hot enough for washing up (this is legal, but it's mighty hot - don't have elec dishwasher); rest of house hot water is regulated to round 50 deg C. Only need gas booster in winter, but then there's waste as gas boosts temp to around 60 deg C and regulator cools it to around 50 for bathrooms etc. You never win !! Ho Hum .... Ric

autogenous
18th March 2008, 06:36 PM
Hit water and Heating/cooling would have to be the highest consumers of power?

I guess it depends how many people you have in a house to justify solar HWS?

Some electric HWS are to be banned?

If only Australia could develop a cheap central heating system that runs with hot water off a solar HWS like used in the United Kingdom?

Plastic hoses and radiators through the house?

Simomatra
18th March 2008, 06:54 PM
If you go solar then consider putting in a one shot switch in the kitchen. The way this works is that it heats water until the thermostat opens, it will then cease until the switch is again pushed. This saves heating water that you don't want to heat.

A timer can also be fitted to normal hot water systems to control when you heat the water.

Hope this helps

I am on my second solar hot water system

echnidna
18th March 2008, 07:15 PM
This is a 5 year old thread blokes.

but something interesting might turn up

rhancock
18th March 2008, 08:58 PM
Well, I read it. And learnt stuff. And its a hot topic at the moment.

I think it is still an area where the guy in the street will not have enough trust in the (mis)information floating around to make a decision to risk a high initial outlay on the basis that you might save it over 3 years, or 5 years, or maybe 28 years! And that's assuming you don't sell the house, or drop dead, or any other unforeseen circumstance.

It is also likely, however that electricity will get more expensive in the next ten years, so you could end up saving much more than you thought.

So it is an area where those people who have motives other than purely financial will be the pioneers.

Simomatra
19th March 2008, 08:26 AM
I forgot to say that the first solar only lasted 7 years and started having problems that they could not fix. It was a top of the line J type Solarhart. I am not impressed with them or their service.:((

They did not get the next one it is an Edwards and pumps out heaps of hot water, only occasionally do we need to boost.:2tsup:

We actually had to get the plumber back to fit a temperature valve to stop it dumping the water of an afternoon in the summer due to the high tank temperature

Forgot to say that mine also has a temperature read out in the broom locker so we can always tell what the tank temperature is. This is the beauty of having been in the electrical trade and able to pick up bits at the right price.

Any comments Al on how yours is fairing nearly 5 years down the track?

patty
19th March 2008, 08:47 AM
I was contemplating Solar but got talked out of it by a installer who sells them as well and he referred me to the heat pump units and so far i have saved roughly between $70- $90 dollars per quarter on my electricity bills