Hot water, under pressure!

14 May

When we moved into this house we realised that the hot water system was 19 years old. That was more than a year ago now, so the (electric, storage) unit has now clicked over 20 years of age – an amazing lifetime for a hot water system.

A couple of weeks ago we ran out of hot water. It was in the evening, so the kids had a coolish bath and it was no real problem. I’ve noticed since then that we’ve been running low pretty regularly, and now today I ran out during my morning shower. That’s getting pretty ridiculous considering we have a 400(ish) litre tank and it is supposed to heat overnight.

So I’m facing the very real possibility that the system has died completely, and I won’t have any hot water in the morning. Not the type of problem you need when you’re 9 months pregnant, and the family is due to stay with you.

So I spent part of the day today calling around for quotes and asking friends for advice. I think I’ve concluded that some sort of gas system is preferable to the ancient electric storage unit that we have currently, but what type?

An instantaneous gas system sounds appealing from a child-safety perspective, but a gas-boosted solar system is much better for the environment.

The problem is, the solar options cost an absolute fortune. For a gas system of the appropriate size I’m looking at $1,500, but for a gas-boosted solar setup the cheapest quote I heard today was $4,500, and I’m not sure it even suits our needs entirely. The gas-boosted solar system with the instantaneous gas booster (my preference because you can control water temperature by outlet for child safety) would set us back almost $7,000.

I’m sure that the solar systems would be great from an environmental perspective, but the hot water component of my electricity bill is only about $75 per quarter. The absolute maximum I could save is $300 per year – so I’m unlikely to recoup the extra upfront cost over the entire lifetime of the system.

At some points in time I might have been tempted to close my eyes and just pay the extra cost, knowing that over 10 years it would be close to break-even and I would be doing the environmentally-responsible thing. But I’m going on maternity leave this week and I don’t have a lazy $7,000 lying around.

Am I being irresponsible? Does anyone have any words of wisdom for me?

21 Responses to “Hot water, under pressure!”

  1. Michele May 14, 2012 at 7:34 pm #

    You’re fine. You do the environmentally responsible thing in many other ways so I wouldn’t worry. There’s no point putting yourself under extra pressure – especially with a new baby about to arrive! It’s all about balance isn’t it πŸ™‚

  2. Liz May 14, 2012 at 8:21 pm #

    How much better for the environment is a gas boosted solar system anyway? My understanding is that you are already saving 3 tonnes of greenhouse gas per year by switching from electric to gas so I wouldn’t worry about the little bit extra (less than 1 tonne per year) you would save by switching completely to solar. Perhaps spend a small part of the $$$ saving on going with gas on switching to 100% renewable power with your electricity provider if you don’t already do that. Either way I wouldn’t feel guilty – if you can’t afford it you can’t afford it, it aint your fault the government chose to stop the subsidies.

    • L from 500m2 in Sydney May 15, 2012 at 3:53 pm #

      I had a lovely guy out to quote me this afternoon, and his opinion was that solar isn’t a good match for our house anyway. Instantaneous gas seems ideal for our situation. Switching to a percentage of green power sounds like a great alternative.

  3. Robyn May 14, 2012 at 8:55 pm #

    Well the gas is better than electric to start with and then you’re going to have a baby soon, which will probably mean bye bye to the 20 minute showers for a bit, so no problem, right?

    To be honest, I think you’ll find that the environmental difference between the solar and gas isn’t that great that you need to lose sleep over it.

  4. Barbara Good May 14, 2012 at 9:12 pm #

    I agree with Liz, how much extra environmental savings are you really making going 100% solar. I can’t believe it’s that expensive! You can only do what you can do, anything beyond that is not something you should feel guilty about. So relax, enjoy a nice hot shower and put your feet up for the last days/weeks of your pregnancy (well as much as you can with two other children in your care).

  5. Mick May 15, 2012 at 7:42 am #

    My opinion is that solar hot water is the biggest thing any household can do to reduce their energy usage. Electricity for hot water made up over 60 percent of our total bill (I know this because it was on a separate off peak tariff) and a year after it was installed, we had reduced our energy demands for hot water by 77%.

    It sounds like you are not only environmentally focused, but also financially focused, so make sure you do the sums and you work it out over the lifespan of the unit and see if that makes it more appealing. Also make sure that all solar credits and rebates are accounted for.

    Also make sure you are also comparing apples with apples. There was $700 difference between a stainless steel tank, and an equivalent vitreous enamel tank which needs a plumber to come out at $400 a pop every 5 years and replace the sacrificial anode.

    We now use so little electricity that it doesn’t matter to us if electricity prices double over the next 5 years, because two times bugger all, is still bugger all. Anyone who imagines that electricity prices will get cheaper over the the years is dreaming, in my honest opinion.

    But, if you have a baby on the way and you need the cash, then do not beat yourself up for having to go for the more immediate financial saving.

    • L from 500m2 in Sydney May 15, 2012 at 3:58 pm #

      Thanks Mick for your thoughts. Our hot water is metered separately too, which is why I know it is an extremely small percentage of our overall usage (probably because it’s off peak).

      After speaking to the person today about solar (and it was in his best interest to sell me the $8,000 system) it seems that switching to gas is probably the most environmentally-responsible thing we can do at this point because of the massive tree that shades the north-west of our roof. Investing a lot of resources (financial and natural) into solar cells etc that are not going to work efficiently doesn’t seem so smart.

      • Mick May 15, 2012 at 8:51 pm #

        I would agree, Solar does depend on excellent solar exposure. You don’t want any shading at any point in the day.

  6. Lilian May 15, 2012 at 9:44 am #

    There’s always going to be guilt but I think sometimes we carry the whole environmental thing too far. It’s not wise to be spending $7K when you know that it’s outside the budget. Far better to stick to what you can afford and live within your means. If you’re really concerned about the whole solar thing, I know energy companies who you can opt in to environmentally friendly power (and in stages according to what you can afford – I can’t remember the exact figures but you can opt to have 25% wind/solar power, 50%, 100% etc). We did consider the whole solar panel thing for our home but we couldn’t justify the initial outlay so we’re contemplating buying environmentally friendly power instead from our energy supplier – and in stages so we can control our costs – it’s a lot easier to judge because we know how much energy we’re using and then we work out how much more we can afford to pay for environmentally friendly power. This way they deal with maintenance issues (and there will be maintenance issues with solar panels) and we work within our means. That’s how we’ve done it anyway.

  7. Alisa May 15, 2012 at 11:05 am #

    Hi, we have a instant gas hot water, and between that and the hot plates that are gas, our gas bill per quarter is usually between $40-$70. We have three kids. I would also love solar however I would have to have it for a long time to get my money back. We set our temp at about 40 degrees so we need no cold when showering and the bath is at a nice temp. regards Alisa

  8. L from 500m2 in Sydney May 15, 2012 at 4:06 pm #

    An update – we had hot water this morning so the old system isn’t completely dead. We’ll still replace it because we can’t rely on it any more and the child safety features of the instantaneous gas are worth the upgrade anyway.

    The person that quoted recommended the Rinnai 26L/min instantaneous system over the equivalent Bosch that I was favouring, even though he was an agent for both. The reason being a few specific warranty/maintenance issues with the Bosch that Bosch haven’t yet resolved. Just one person’s opinion, but he was honest to his detriment in other respects, so I trust his opinion.

    • Alisa May 15, 2012 at 4:17 pm #

      We have the rinnai 26 as well. We had it put in 6 years ago and still going strong. One suggestion is if you have a choice put a temp controller in both the kitchen and the bathroom. We only have one in the laudrey and if I did it again I would have done the extra controller. Regards Alisa

  9. Lilian May 15, 2012 at 4:34 pm #

    As an aside, if you haven’t already done so, do a search online to compare energy providers. I found a better deal and then rang my existing provider to ask if they could match it and they did. If I hadn’t asked I would’ve still been on the same plan – now they’ve given me 12% off electricity and 8% off my gas.

  10. sydfoodie May 15, 2012 at 6:06 pm #

    The downside of the old electric 400l system is that you are heating the whole tank of water. This why they introduced ‘off peak’ electricity rates and now I don’t think you can buy them anymore.
    +1 instant gas
    +1 extra controller in the bathroom

    -1 solar gas boosted, especially since your long term plan for the house is to extend upwards.
    -1’green power’. Don’t bother, it’s a rort, and it hasn’t actually contributed to green flavoured electrons. If you really want ‘green’ you would do better to invest in the actual green producer such as a wind farm.

    • L from 500m2 in Sydney May 15, 2012 at 7:32 pm #

      Thanks for your thoughts K. I think I’ll be ordering the instant gas tomorrow – ran out again this evening.

    • Liz May 16, 2012 at 8:44 pm #

      My understanding is that some electricity providers such as AGL & Origin are also producers – ie they develop, own and run wind farms etc. Under those circumstances doesn’t buying ‘green power’ from them count as investing in its production? Maybe I’m wrong or being naive though.

      • sydfoodie June 21, 2012 at 10:04 pm #

        Origin and AGL have interests in gas. To me, gas is not a “renewable resource”, because they have extracted it from the ground. It is all too often associated with coal mining.

        Regarding their interest in “windfarms”.

        http://ramblingsdc.net/Australia/WindNSW.html

        Origin own Cullerin Range Windfarm, purchased off Epuron in 2008. It generates 30MW total.

        They bought Snowy Plains windfarm, which would have had a capacity of 30MW, except that that they decided not to go ahead with it.

        NSW peak winter demand is of the order of 13 GWH, or 1300 MW.

        I’m not sure what percentage of the population pays for green power, but how does 30MW offset 1300MW?
        It’s out by a factor of 40!

  11. sydfoodie June 2, 2012 at 7:11 pm #

    I just came across a choice article (July 2011 paper edition) that recommends for houses of 5+: “you’ll need larger tanks and with potentially bigger savings to be made, the upfront cost of going solar may be less daunting. For these households, gas storage units may be more economical than instantaneous systems.”

    Also that with instantaneous ” capacity is determined by flow rate in l/m and depends on the number of hot water outlets the heater has to serve. For a two bathroom house you typically need a flow rate of 22-24l/m. A small house may need one unit, a larger home two or more.”

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