Viability of Solar on Average Family Home

Hey guys,

I know this theme has been flogged to death but just wondering, particularly in light of recent la Nina weather and rain, if those of you with solar and no batteries are still getting big enough savings on your power bills to justify the outlay

We use about 24kwh daily. I'm imagining half of which is probably at night, and am tossing up the viability of a 6.6 or 8kw system.

Given my family contains a green energy hating boomer, the numbers must be compelling for me to win here lol

I'd probably need to at least halve the power bill and maybe a 5 year or so break even period to get it done.

Thoughts appreciated :)

*I'm in NSW

Comments

  • Location? Estimated cost of installation?

    • Hi. I'm in NSW. Based on a quick Google the 6.6kw systems are around $6000-$8000 and the 8kw systems are about $8000-10,000

      • Are you in a metro/large city or a more rural area because it can add ~20% to the installation cost.

        • Newcastle NSW

  • Can you move some of your consumption to day time?

    Personally, we are very happy with our solar installation. Here are our numbers for the last 12 months.

    Energy Consumed From Grid: $363.57
    Energy Consumed From Solar: $252.66
    Energy Exported to Grid: $719.29

    Net Energy Savings: $971.95 ($252.66 + $719.29)

    Total Energy Cost over 12 months: $69 credit. ($363.57 - $719.29 +$286.62 supply charge)

    So, we have had zero electricity cost over the last 12 months - in fact made a little bit of money. Compared to not having solar, we have save nearly $1000.

    We spent over $8000 on the unit; so are looking at about 8 years breakeven. With prices going up, may even break even a lot quicker as most of our consumption is during the day.

    • Hi Mr Hyde,

      Can you remember your approx daily usage and the size of your system?

      And yes, I'd definitely do all the washing and drying and pool filter during the daytime if I had solar.

      And with the way it's going I'd say power prices will probably be double in 5 years too. So might pay for itself faster

      • Updating your Pool Filter can also help save $$$

        Speak to Jackie at Access Pool Services Warners Bay.

  • +1

    Our system is 6.6KW and daily usage varies. Winter months, we use about 16kwh. Summer months, it is about 4 kwh. Majority of our energy use is heating. House stays cool during summer, so almost no air conditioning.

    Second highest user of energy is the oven. Everything else is pretty negligible.

  • How many people WFH?

    • +1

      Hi. Generally 4. No work from home. I'd say we'd use more energy at night with heating and TVs, computers etc.

      Aircons could be used during the day to lessen the night costs if we had solar.
      Same goes for washing, dryers etc

      • -1

        Maybe you should add the cost of a battery to hedge for night use and for when the gov removes FIT.

  • -2

    The way it's going we will be getting $0c FIT, and higher kwhc, so unless you are using a lot during the day, and like OP said the amount of rain I would say no.

    • +1

      You would be badly mistaken, and will pay higher bills than necessary.
      6kw will average 24kWh generated per day.
      If op uses half that to offset their daytime use it will save them around $3 a day. They will make a little more from grid export.
      If they can move a little usage from night to daylight (running dishwasher or pool pump or washing machine or whatever) that might add another 50c a day with not much hassle.

      This adds up to more than $1000 a year benefit. The system is paid off after 6 years or less. They will keep earning that for 10- 25years.

      You could easily save the cost of a new car over the life of a system, it isn't in any way trivial.

      There is no question op will be much better off.

  • -2

    No way I would pay $8-10k up front for solar, we did our's 5 years ago on 2 years interest free which meant we got it for $0 as the money saved off the bill which we would of payed anyway payed for it.

    • +3

      on 2 years interest free

      no, the interest and finance fees were just factored in to your solar installers price…

      • -6

        yes, was same price as other quotes, go away

        • +2

          Someone pays the finance costs.
          Financing isn't free.

          You have said in the past you lease vehicles, overpay for scuff plates and earned thousands before breakfast…. You can't be this uneducated about how financing costs are calculated and how they can be accommodated within a pricing structure.

          Sorry to burst your bubble, but you paid some additional cost for that interest free..
          perhaps you used those immediate funds in a more beneficial way to offset those financing costs (such as in an offset account or alternate investment, or perhaps on just overpriced scuff plates), but pretending they didn't exist is stupid.

        • +2

          Your earlier comment says it isn't worth it, yet this comment says you paid of your solar in two years?

          • -2

            @mskeggs: see ya

  • +2

    Surely it’s a no brainer to get some sort of solar. Yes, there’s been a lot more cloud cover in event months but when the sun shines you get ‘free’ energy. won’t drop you bills to zero unless you don’t use power after dark, but even running a pool pump off the sun will be a saving.

    Is it possible to orient some panels to the west to get more power later in the day?

    Don’t just aim for the biggest you can get, get someone to optimise the system for your usage. Paying $2k extra for a bigger system may not be worth it if all the extra power is going out to the grid at low rates. Then again, pumping power into the grid will (eventually) reduce daytime power rates for everyone.

  • -3

    Installed a 6.6kw System 5 years ago. Bill was virtually nothing for the first 2 years and that paid for the system. FIT prices have dropped significantly in the past year plus the rain would not be worth it installing today.

    • +5

      Except that it’s not going to rain forever and power prices will continue to increase while coal
      Is base load. The payback period will probably be longer

      It’s not as simple as having rain and low feed in. It’s good to have some autonomy from grid pricing and limits.

    • +5

      Astonishing that you paid off a system with a 20 year life in two years, but conclude you wouldn't do it again because it is rainy and FITs are lower.
      How did you reach this conclusion?

  • +3

    Got a 6.6kw system (inverter is 5kw so output limited to 5) installed April 2020 and haven't had an energy bill since. I paid $5000.
    I originally got FIT of 21c from AGL but that contract expired after 2 years (like just now! FIT is now 10c) and only now am I slightly out of pocket. I never paid an electricity bill since then and with the FIT my bill was always in credit!

    The credits I got on electricity paid for my gas bill - I just needed to contact AGL to transfer my electricity credit over to my gas bill.
    But my very latest gas bill which just arrived last week was too high to be covered by my electricity bill credit. Oh well, I'm like $50 out of pocket.

    I am not far from Newcastle and PV panels are on a north facing roof without shadow so in a great pozzy. The only dips I get in generation is when a cloud(s) blocks the sun.

    But my household is smaller than yours so consumption less.
    I'd still say solar is well worth it. You just need to shift most consumption to when the solar is working best - when the sun is shining.

  • +1

    Bigger is better…

  • -4

    Not worth it, I got Solar when it was free but it has meant my roof has degraded faster in the areas where the panels have been installed. I have had to get leaks fixed several times, but it is finally fixed.

    From what I recall it worked alright for the first few years but then it caused too much pressure on the roof in some areas.

    Circa 2009 if I recall. That was only a 1kw system, imagine what a 6kw system would do to your roof. This is why I recommend getting those tesla tiles instead if you are going to do this.

    • +3

      Technology has advanced a long way in 13 years

      • Are they lighter now? Damn, I got screwed. I couldn't even remove the solar panels and dump them because I wasn't sure if I had passed the amount of time required for the RECs.

        Yeah, lol. I forgot I already mentioned Tesla Tiles, but for the normal ones, has that gotten lighter too over time?

      • How advanced is PV now?

    • +5

      20kg per solar panel mounted on frame that sits on top of your roof battens. A 1kw is like 4 panels at 250w each. Suspect either a bad installer or something wrong with your roof.

  • Those saying they don't get a bill with solar must use FA anyway so wouldn't be worth it.

    • No, they might just be on a better feed in tariff

      • not for long

        • That doesn't mean they are lying when they said they do now and in the past

          • -1

            @Quantumcat: will see

          • -3

            @Quantumcat: ps and go away I didn't mention anything about them lying

  • +2

    Family of 4, in Adelaide,
    12.4c/kW Feed In.
    5kW system 2kW North (Shaded until 9am), 3kW West (Shaded until midday), we pay $300ish/year, basically the grid connection fee.
    (Gas Hot Water and Heating)

    I have a whole home energy meter and that tells me we consume just under half of the power we generate, without really trying to time-shift our usage to the day time.

    Ideally for a family out of the home through the day you'd get something like 2.6kW Easterly and 4kW Westerly panels installed as that's when you're most likely going to be home consuming power (Morning - Cooking Breakfast, making coffee/tea, and then Afternoon - cooking Dinner, Heating/Cooling the home)
    Without the shading issues, we'd be close to $0/annum I reckon as we get burned in our morning usage due to the lack of generation from our unavoidable shading issues.

    On the Rain at the moment… It's Autumn/Winter, it's always cloudy/rainy no matter whether there's a La Nina or El Nino… and there probably will be an El Nino again. We pay $170ish/ quarter through the Winter (Shorter days as well as more cloud) months, and get paid a little through the Summer Months to bring the total back down to $300ish/annum

    If you have an unbeliever, get them installed in Spring, so they see the benefits upfront before the Winter months kick in and you actually see a bill again…

    • +1

      Should have specified, we consume (yearly average) 14kWh/day
      Lets see how this data table comes out…

       ....... Consume Total  Consume Solar   Import  Export
      

      May-22 ……. 11.78 ……. 4.12 …………………… 7.66 ……. 8.55
      Apr-22 ……. 11.08 ……. 5.08 …………………… 6.00 ……. 10.42
      Mar-22 ……. 14.44 ……. 8.12 …………………… 6.32 ……. 15.78
      Feb-22 ……. 14.24 ……. 8.52 …………………… 5.72 ……. 18.60
      Jan-22 ……. 19.28 …….12.38…………………… 6.90 ……. 15.80
      Dec-21 ……. 13.74 ……. 9.22…………………… 4.51 ……. 24.24
      Nov-21 ……. 12.52 ……. 7.53 ………………….. 4.99 ……. 19.94
      Oct-21 ……. 11.62 ……. 6.60 ………………….. 5.02 ……. 19.05
      Sep-21 ……. 11.98 ……. 5.10 ………………….. 6.88 ……. 14.61
      Aug-21 ……. 12.16 ……. 4.48 ………………….. 7.68 ……. 11.21
      Jul-21 ……. 14.39 ……. 4.22 ………………….. 10.17 ……. 5.81

  • +3

    I'm also in NSW and had similar consumption as yourself. I had my 6.6kw system installed in Oct 2020, costing around $2800 (other quotes were around $4500). To date, my quarterly bill has reduced by around $300, meaning a payback in around 2.5 years. It was no brainer for myself.

    However, the economics for batteries don't add up at the moment but that may change in a few year's time when FIT drop to 0, battery prices come down (hopefully) and kwh prices increase further

  • +1

    I'm in Sydney Metro. I got my 6.6kW (5kW inverter) solar system in 2018 for roughly $5000 (way cheaper now). 1-2 persons household (6-10kWh daily usage) and already we saw a reduction in quarterly bills from $400ish to $100-ish (credits during hot summer months). Savings will be greater with bigger households and bigger systems. Another benefit to having solar is the guilt-free freedom to turn on power-hungry appliances in the day.

    I personally think it's a no-brainer to get a solar system installed, although battery is still not cheap enough to make it a non-brainer.

  • Got a 5.5kW system in Brisbane about 4-5 years ago for just over $7,000. It paid for itself in ~3.5 years with considerable savings from the electric hot water being controlled by a relay in the inverter when the sun is shining. Overall it's been using 50% of the power generated at home, and it's generated roughly what the installer predicted it would. I'd do it all again without question - but with a bigger system today.

  • Go for 6.6kw move as much of your use to day hours as possible if you are not going with batteries. No point selling it back to the grid as the powers that be are being funny about paying people return on money invested.

  • +1

    OP, consider solar as a 15-20 year investment and get the largest system you can afford today

    1. There will be pain from July once the reality of the increased wholesale power prices hits - this will increase solar demand
    2. The new government strong supports renewable energy - they will increase solar demand
    3. Our solar industry is heavily dependent on one country and according to the news, relations are getting worse every day - this will increase solar prices

    If you want to be brutal, tell the boomer the benefits will outlast their expected lifespan (this is a joke but you get the drift…)

    • Our solar industry is heavily dependent on one country and according to the news, relations are getting worse every day - this will increase solar prices

      This is a very good point, if we end up in a war with China it will be very expensive if not possible to get a solar system installed then. Better to do it now while we are on ok terms with them.

      • +1

        China will keep selling us stuff to fund their war chest. When war starts we'll be left standing with empty shelves at Kmart and Big W.

  • +3

    Adelaide here - reasonably high consumption, stats for our 6.6kw panels over the past 12 months:

    • System Production: 3905.1kWh
    • Load Consumption: 6153.3kWh
    • Self-Consumption: 3530.2kWh
    • Imported From Grid: 2623.1kWh
    • Exported To Grid: 374.9kWh

    57.37% of our power was self production
    42.63% was imported from the grid.

    This suggests that we have reduced our power cost by nearly 60%.

    • -1

      I would suggest most of your imports would be after sun goes down or on the rare chance you are drawing more than the panels can supply.

      Averaging 7kwh from the grid. Might be worthwhile looking at a battery to cover some of that.

      I am looking at small size battery to cover sunset to 11pm when off peak kicks in.

      • +2

        They’ve only exported 374.8kWh over a year, so no point getting a battery as it would never be charged!

  • +1

    In WA we get a measily 2.75c/kw feed in until 3pm before increasing to 10c/kw after.

    Purchased my 6.6kw system for $2200 and expect it to pay itself off in 5 years, currently at 90% export (no air-con, if you run aircon it will virtually pay for itself).

    We generate roughly 2500kw a quarter from memory and consume maybe 10% of that.

    Due to the low feed in tariff the net result is an energy bill of zero during summer, which i'm happy with as it results in a yearly energy bill of roughly $200.

    It's a no brainer if you can find a system for around $2500-$4000

    $8k is way overpriced.

    Also FWIW the energy grid in WA is in much better shape due to lack of privatisation so i'm ok with the low FIT
    The governments over east have screwed their people by privatising the energy industry, with no provider willing to own the shortages in the grid yet happy to profit from it when they see fit. Privatisation does not equal cheaper or better quality when its a basic right at stake.

    • @Drakesy would you be keen to let me know who you got to install? Looking to put for my mom and put in 5yrs for over $8k which now I realise was a rip

      • Emerge solar
        Had a deal on ozbargain about a year ago I believe

        • Cheers. Will keep an eye out

  • we have 12 panels on our roof, in Sydney metro (Ryde) with no obstructions. We are signed up with AGL and each quarter we get sweet Bugger all difference to our bill from the solar installation. It's been cleaned and checked, but till we're luck to get $50 a month from it.

    • This whole year has been bad for solar generation in sydney, I bet we have had more wet days then dry

    • I have 10kW panel on our roof, Sydney metro. First quarter with solar (Dec - Mar) we saved approx $400 compared to last year, second quarter currently I project we would save $200 compared to last year.

      We do consume a lot due to lots of cooking, heating and drying clothes with this La Nina, I think average 30kWh during Sping/Summer and jumps up to 45-50kWh during Autumn/Winter, but we don't use gas only electricity. I paid a little over $9,000 last year as it's high quality Q.Cells Duo panels and Fronius Inverter, so projecting approx $1,200 saving a year with this La Nina is not so bad.

      • How was the company you went with? Am about to start researching myself. We have limited roof space and itsmostly West/East.

        • They are gold supplier on Solarquotes and has been around for 10+ years. Seems decent, took about 2 weeks after paid deposit for installation, work looks decent and there was some issues with Fronius smart meter which they quickly came back to fix. Our roof is also West/East and the panels are distributed evenly so I have solar throughout the day.

          • @Bigboomboom: Thanks. Our use case is probably somewhat similar to yours, if not now is heading that way, in terms of consumption. I had been holding out for pricing to be a quicker return on investment but its gone the total opposite direction and now prices appear to be double what they were 2-3 years ago. How bad retail pricing gets i guess will determine whether we bite the bullet.

            • @Xizor: Rebates is reducing while price has gone up somewhere between 15%-30% unfortunately, compared to when I got mine last year (October order and 1st week of November installed). However electricity wholesale price is also going up.

  • sign up for open solar, the app is pretty darn good and what a lot of solar installers use. its not that hard to learn to use either.

  • Around a quarter of your electricity bill is for hot water.
    If you don’t go “full Solar”, at least get a solar hot water system, which pays for itself very quickly.

    • I think technology has advanced enough now that you are better off getting a solar panel system than getting solar hot water (evacuated tubes). Solar hot water doesn't cover all your hot water needs, it often has to be boosted with gas or electricity anyway and that roof space would yield a better return with solar panels instead

  • +2

    You live in Newcastle, a 6.6kW system would generate on average 27kWh a day (assuming fully north facing).
    Lets assume from that 24kWh daily usage you can self consume a modest 30% of your solar production
    And from what I can see the cheapest power rates in Newcastle are about 20c kWh.
    So 7.2kWh x 20c =$1.44 saving from self consumption.
    Looks like the current standard FIT in Newcastle is 7c.
    You are exporting the remaining 19.8 kWh to the grid at 7c =$1.38 export
    Average daily saving is $1.44+$1.38= $2.82
    $2.82x 365 = $1029.3 annual saving from solar.

    I haven't kept up with current solar prices but a 6.6kW system pre covid was 3-5k after STC rebate was taken into account.

  • +4

    I feel like somebody dropped off a bus load of patients from the head injury ward judging from some of these comments.

    People saying they paid off their solar in 2 years, but that they wouldn't do it again. Amazing.

    If you own your house and get sun on the roof, just get panels and save some money.

  • +1

    Some very good calculators on the Solar Quotes site. They have solid info that you can use to look at your own situation.
    Solar definitely worth it, La Nina is irrelevant.
    Insulation, led lighting, managing your site aspect are all part of it. At 24 kWh if you can reduce your use by 20% that is basically your Solar system without installing it.
    You need to stand back from just Solar are look at energy management for your home as a whole, and maybe Solar as part of it.
    For example: if you get rid of all of the draughts in your house with decent seals etc you can possibly drop your energy use by 10%. 2.4 kWh for less that $1k. Change your lighting to LEDs, that could also knock 5 to 10% off, if you still have halogens. Insulate. Manage northern aspect for winter sun and summer shade.
    Do this sort of thing as a cost benefit exercise where Solar fits a cost point among other stuff.
    Educate yourself about home energy management. Or just keep paying…

  • From the calculations I've done for my personal circumstances, solar power would just pay for itself by the time it's out of warranty. So if I was green, I would do it, but because I'm more lazy than green, I haven't.

    I've been hoping for a good deal to jump on, but if prices rise I might eventually be forced into a crappy deal.

    Battery systems aren't affordable yet. I would jump on that if they would pay for themselves.

    • +1

      Warranty isn't the expected end of life of a system…
      Warranty is an indication of the quality of installation and nothing more.

      It's completely illogical to assume otherwise.
      Even assuming 5 years past warranty you'd be ahead. Plenty of examples of systems that are 15+ years old and running fine, it's not like this is unknown tech with unknown reliability!

      • -1

        Let me guess - you're on the green team.
        I'm sure there are plenty of examples of early failure too.
        You're very optimistic and have an expectation to not need a warranty, I guess I'm a pessimist and wouldn't put my money on that.
        You say I'm completely illogical, I say you are. But that's fine.
        If I get 5 years more than warranty, then I'll be happy. But if I don't, I won't be disappointed.

        Am I missing out at the moment? Maybe. But considering the opportunity cost of the investment, I don't think so.

  • +4

    I'm in Tasmania with 6kw West facing panels on a 5k inverter. Cheap $4k installation from Captain Green. Also got my gas cut off and bought an electric inverter water heater. Haven't had a bill for 2 years. Change from gas hot water to electric was also $4k for me because I required electrical work and tank installation etc.

    Heating is heat pump, 3-4 people in house, we didn't modify our behaviour much but I try run dishwasher and washing machine during day time. Feed in tariff about 10c ATM.

    I am a disability Pensioner and get significant power discounts and rebates, but before I had solar I always got bills of about 80/ month for gas and about $100/month for electricity on average. So I'm saving about 2k annually now.

    Now of course I didn't have the 8k to invest but the covid 'mortgage holidays' allowed me to get it!!! My mortgage payments have not really changed since, maybe my principle has a tiny bit, but who cares, life is much better now without bills of hundreds of dollars coming in regularly!!!

    • Well done! True Ozbargainer 👍

  • It’s a no brainer, just do it. Had it done last year and haven’t looked back. Break even, probably 3-3.5 yrs. Should’ve done it sooner.

  • Problem is there is no such thing as an "average family home"!
    We have infinite diversity and infinite combination, and so many different use cases for solar.
    Peoples requirements change continually also.

    This discussion is about whether solar can save money for an "average family" - it is really just an investment with a long payback.
    As a correctly installed solar system should last 10-25 years with almost zero additional expense, it almost cannot fail to create a positive return.
    Yes there are cases where peoples roof is not suitable, cases where people pay too much, cases where people have to include finance costs, all these should be considered if you want to make the correct decision.
    Your best case is saving a couple of dollars a day, less than a cup of coffee, but over 10-25 years (3,650-9,125 days) its a good return.

    Figure out how much roof space you can use, and use some of the calculators over at solar quotes to figure it out.

  • No point in looking at the venture for one season therefore this year's rain is relatively insignificant.

  • Yes get solar, no brainer. And get some help with minimising your electricity use. My household of 2 use 5kWh per day over most monthly billing periods. For months of Feb to March my usage was a measly 125 kWh generated and 82kWh used. I have an old old 1.5 kWh system and premium FIT. In Victoria.
    25kWh is really high IMO. You can get it down.
    Look at your useage rates on your suppliers website and get a free time of use energy monitor.

    • 5kWh a day? lol my spa uses more than that. We are 2 ppl use 20-30kWh or so the bills say.

  • +1

    1) Energy prices will always increase along with time - this is certain. Unless we find a cheaper than nuclear alternative.
    2) If you install lots of panels now, you have mitigate part of the future price increases
    3) Winter output is very low, but Australia get lots of sun most time
    4) Panel prices may go down but will be offset by higher energy cost. It may even increase due to more China lockdown.
    5) Look into your day and night usage. There's no sun at night.
    6) Powerbank are expensive and they will wearout.

    I would recommend solar installation if you can afford it whether if it helps with your bills or not. Using your unused roof as a green energy source is really helpful for a sustainable future. Solar on roof is a very simple system, if it stops working you can just flip the disconnect switch and get it fixed when you are able. Plus there is no moving parts so extremely low maintenance. It just quietly absorbs the sun then feed the inverters and hopefully keep money in your bank.

  • Don't forget a 5KW system with over 5 hours of sunshine can generate 25Kwh in one day.

  • Would love some advice on solar panels. Being thinking of getting them but don’t know what size to get.

    Moved in to a duplex in South East Sydney about 11 months ago (lived in a townhouse before that so couldn’t get solar panels). Roof is fairly flat, slightly angled I think.

    We use LPG cylinders for hot water and stove. Use about 1 cylinder per month. Have ducted air con and with 3 kids the washing machine and dryer get a workout. Use both a lot at night during the week.

    Our daily electricity consumption since moving has been,
    July 21………29.36kWh
    Aug-Oct 21…21.87kWh
    Nov-Jan 22…15.80kWh
    Feb-Apr 22…15.63kWh

    Based on this, what size solar system would I need? Any advice appreciated.

    • Get the biggest you can fit, and upgrade to heat pump hot water and electric cooking and dump the LPG cylinders which must be costing you a fortune

      • +1

        Thanks @Quantumcat. LPG cylinders are costing me $164 per month. Heat pump hot water…I’ll have to google that.

  • If your energy prices haven't gone up yet, they very soon will.
    Wholesale electricity prices have risen so much in the last few weeks that many retailers are asking their customers to leave as it is costing them too much to keep them.
    The price increase is primarily due to the Ukraine invasion & the old coal power stations here continually breaking down. Neither of which will have a quick fix, so high prices can expect to be around for a few years.
    Get the biggest solar system you can, the incremental cost to get the next size up isn't that much. Then in a few years when battery prices come down, your extra solar capacity will make big cost benefit on the battery install. Additionally, if you have gas, you can gradually move to switch that and replace appliances with electric as they breakdown.
    The long term vision should be to electrify everything, eventually your whole house & car can be powered from solar & battery. Australia still has a few years to catch up on this, as usual we are lagging a bit behind the rest of the world

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