We're building a house next year and will probably install solar PV. In our previous house we had continuous gas water (NG connection) and enjoyed the comfort of knowing that our kids wouldn't use all the hot water (which happened recently in our current house).
Is it normal to have solar PV and continuous gas hot water or is it generally considered a waste of money?
that's old tech using sunlight to heat up water in the glass tube. If OP is building I'd suggest he install solar panel for electricity and heat pump tank, just make sure getting the bigger tank enough for the family and give some discipline to anyone taking shower more than 15 mins
More cost effective to have a normal resistive hot water tank or heat pump tank. Just size it nice and large so there's enough for 5+ long showers and you'll be fine. I used to have instant gas hot water and loved it SOOO much, but if you aren't having a whole house on gas (cooking & heating as well), which you wouldn't want to if you are installing solar, it isn't worth paying the ~70c a day connection charge.
Mmmyeah. My 'simple advice' (without knowing all the intricate details that apply to your specific situation/location) is to ensure that you have the north-facing roof-space on the house you build to 'house' a 6.6 kW (or greater) solar system, and install a large and very well-insulated electric hot water system/tank. If you are in one of the states that currently has the 50% rebate on batteries (such as Victoria), definitely install one of those as well. With a large hot water tank, battery, and 'feed-in' payback, you will never run short of hot water and you will never be paying for it either.
If you are getting solar and can have hot water on off-peak you will find it is really cost effective - just make sure you size the tank right i.e. 315l for family of 4-5
Instant gas will certainly be bit cheaper if you are anyhow having gas connection.
You can gave solar boosted continuous gas water.
Solar panels heat up waters and stores it in a tank. If the water in the tank is hot, free hot water, if cool or warm, a continuous gas booster makes up the difference.
Best of both world.
In Melbourne, I'd estimate the sun heats up our hot water for half of the year. Our Gas usage are virtually zero between Nov to March. I'd say most of our gas usage is for heating
anyway.
On sunny winter days it still heats up the tank.
I believe heat pumps run off the PV with a gas booster are the most economical at the moment.
Solar hot water systems i believe are quickly being replaced by these.
I believe heat pumps run off the PV with a gas booster
Just trying to understand why you would need a gas booster with electric heat pump HWS?
Wouldn't it be ideal to get rid of gas completely?
Sanden, Reclaim - two of the most popular heat pump HWS don't use gas boosters.
PS: I did not neg you. :-)
Is it normal to have solar PV and continuous gas hot water or is it generally considered a waste of money?
Exactly what I have. The solar credits I get for feed-in to the grid means my electricity is in credit each bill. I then offset that against the gas bill. I have nil bills for any energy.
Thanks all. Looks like we'll go solar PV with electric/heat pump HWS and ditch the gas (the insurance of not running out of hot water may not be worth paying the connection fee).
You don't want Gas for heating or Cooking?
No, going with induction and AC. A gas fireplace would be nice though! Might have to go with firewood.
Fair enough..
I also have induction but prefer gas heating.
No PV solar yet.
Shorts, re:
'Might have to go with firewood.'
Do a bit of reading about long-term effects on the lungs in this regard. There's also the fact that burning wood is about a bazillion times worse for the enviro-nen-ma-ment than any other form of heating known to humankind, but that is not really something I focus on (I'm far too old to worry about such things). Do check out some of the recent studies pertaining to the potential effects on the (lung etc.) health of those living in houses heated via burning wood though. I advise against it. 'Amping up' (soz) your solar capacity/credits to enable economical electric heating would be infinitely preferable in my humble opinion; particularly if there will be kids living in the house for many years to come.
Great choice. I did the same. Ditched gas completely. Use an Induction cooktop for cooking (cleaner, lesser energy waste and no toxic fumes compared to gas) and reverse cycle AC for heating AND cooling. With my feed-in credits, havent paid a bill yet.
I'm confident this will be the norm within a decade.
Do you have electric hot water or heat pump?
Heat Pump. I set the HWS to heat water only during 12:30pm-2:30pm, so essentially it costs me nothing as I will mostly utilize electricity generated from my PV system.
@0FoxGiven: Do you know if the same can be done on an electric HWS even if the HWS is set to an off peak tariff?
@ShortyX: Dunno mate. It can't be done with instantaneous type HWS obviously. Not sure if other non-heatpump storage tank HWS have such fucntionality
@CheapSticks: Chromagen. Not a brand I would have preferred but it was what I had to go with because my builder only sourced from that brand. It was a $200 upgrade from the gas storage tank the builder had as an inclusion.
For me (having a mains NG connection) I love the ability to set my hot water temperature on my Rinnai. Shower - 38 degrees, turn the hot tap on and go. Dishwashing - 50 degrees turn the hot tap on and go. We have a temperature pad in the kitchen and bathroom. No water or heat wasted getting the right temperature. Tap mixers are kind of pointless in our house now.
I was tempted by induction cooking when we installed our new appliances a few years back but, at the time, there was a ~$2k premium for the equivalent size of the gas hob we got and we have been very happy with gas since (but completely get why some people love induction).
Might have to go with firewood.
Nooooo! Seriously I can't stand wood heaters. They stink out the neighbourhood and leave a hovering cloud of smoke. I can't stand my inconsiderate neighbours who crank up their heaters all day long and their chimneys are spewing out acrid smoke for all to breathe. So much for hanging clothes on the line.
They should be banned. And yeah I know about green wood causing the smoke & seasoned wood shouldn't smoke as much. But idiots who just chuck in any old wood, or find a gum tree fallen in a storm and cut it up for their heater, man they really fire me up. Pun intended.
Best bet - ban them.
I've got gas heating and water, when my appliances die I'll be replacing with electric, I don't see the value in gas anymore, especially paying $300 a year for supply.
Heat pump should be the weapon of choice for ozbargainers. For every 1kW of energy consumed it outputs 4kW!
Are they reliable nowadays? I guess they are quite expensive upfront too.
Can electric HWS be set to use solar even if it's on an off peak tariff?
Great question..am keen to get an answer to that.
I asked abt Heat Pump - quote $5,500 - 5yr warranty - i wont even get my money back within that time period.
Sanden is the Rolls Royce of heat pumps, you may pay around $4k installed after rebates. There are plenty of other reliable brands that are cheaper though:- stiebel eltron, reclaim. Setting up a heat pump to operate during solar hours is best option, however doing the same with a resistive element hws is also a viable option.
Take into account the electricity providers dont like individual solar as it upsets the grid and so are pushing governments away from it.
Latest I read is that individuals will need to pay to feed power back into the grid.
See here:
https://www.abc.net.au/news/science/2021-03-30/solar-power-e…
So do your research first!
individuals will need to pay to feed power back into the grid
Slightly misleading - there will be a small fee. Anyone with a solar system feeding into the grid will still be making profit from the power they feed back to the grid. It's just worth taking it into account when you're working out your payback period for installing solar.
Not misleading at all
Its under investigation.
Solar grid feeding is forever changing
Read the article.
Headline quote:
"Should solar owners pay to supply the grid"
As i wrote:
"do your research first"
I have read the article. If you read more than the headline, you'll see that it says:
The tariff would work "…by charging them in the range of two cents per kilowatt-hour in moments of high demand.
The AEMC's modelling shows a typical solar household may lose $70 of a $970 annual benefit from having rooftop solar through the reforms."
I.e. typical user would still have a $900 profit from feeding back to the grid.
Also looking at replacing the old gas hot water tank with a heat pump or electric as I just installed a 5kw PV.
However, the feeling I get from heat pumps, are that they have high upfront costs but can fail before breaking even. Repairs can also be terribly costly.
The recent deals on this "iStore" heat pump is tempting though, although I'm waiting for more long term reviews on this brand before deciding.
Anyone has experience with heat pumps to share?
Agreed - my hesitation stems from the upfront costs and reliability concerns.
Agree - i was told Reclaim brand is better..need to hv 10yr warranty and then it works in my opinion
Plumber here.
Agree with your no to heat pump for the same reasons as well as many i have attended for noise complaints.
If you’re looking for cost efficient solution in your home, then solar panels can be used to heat water, you do not need to install specific solar hot water systems.
It is quite normal to have a solar hot water system with continuous gas make-up. It's mostly operating on the continuous gas for me during a Melbourne winter.
I also have solar PV.