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Solar Disappointment

(20 posts) (11 voices)

Started 1 year ago by wmeg
Latest reply from Bearamundi

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wmeg
Member

Hi all, just over a year ago I had a 3kv solar system installed. I got a govt subsidy so it cost me approximately $3000 .
I just got my fourth bill so I have been going 1 year and my total credits come to $96.50 and there has been no real discernible decrease in my bill.
I was so shocked at how little my return was that I got the company that installed it to come out and make sure the system was working properly. It was
So if I had paid the full $10,000 I should be square by about 2100.
The thing is that I have 4 a/c units all on tariff 33 and also a pool pump on tariff 33 (this runs at night so it doesn't make much difference).
On a pre installation bill the a/c units and pool pump cost about 30% of the total bill now it is down to approx 15% so that is where all of the solar power is going.
That is another $150 PA to me
Instead of paying 10.29 c/kWh for the tariff 33 I am now paying 50c/kWh because it is using the electricity that my panels are producing.
That never occurred to me when I had the system installed. I will get my $3000 back in about12 years, but I am helping someone,however I'm not sure who.
Apart from going off the grid is there any way around this.

Thanks
Warren

Posted Tuesday 31 Aug 2010 @ 6:36:31 am from IP #
LanceTurner
Key Master

Yep, spend some money on making the house more energy efficient and get rid of the aircon units. I keep telling people that solar PV is the last thing you should do, there's no point installing renewable generation if the energy you generate is just wasted cooling an inefficient house or running inefficient lighting and appliances.

Have you looked at energy efficiency overall in the home? Do you have inefficient lighting like halogens etc? All this stuff should be done first. In most homes, making it more energy efficient can cut energy use in half and in some cases by as much as 70%. The average Oz home is an energy efficiency disaster really, there's so much that can be done...

Anyway, if you come back with some more info on what else has been done to the house then I can make some more suggestions...

Posted Tuesday 31 Aug 2010 @ 6:50:42 am from IP #
Buzzman
Member

Warren
I second Lance's comments above.....always REDUCE consumption FIRST before installing PV.

Are you in a net feed-in tariff are, like VIC?? Cause the GFiT system in NSW works differently....

With a net system, as I understand it, what the panels produce during the day goes towards your daytime consumption - ie: pool pump and A/C units.

But it will also be going towards the fridge, freezer and anything ELSE you have turned on during the day, so you will not achieve 'net export' unless you can minimise the total daily 'daytime' consumption rate.

A 3kW system in VIC ought to be producing around 12-14kW/day, so clearly you are using loads more than this.

My two-person household uses 6.4kW per day on mid-north coast NSW. No A/C. LPG HWS. CFL and fluoro lights. One LCD TV. One PC. Not much else.

And we have weatherboards, zero insulation, and large roof and window areas facing west, so not pleasant during heatwaves, but we manage with fans and damp cloths.

My 'heating' bill this winter was $20. ie: the winter bill was $20 more than the previous bill. 2400W Electric space heater, heating one room only - the one we are in at the time, like lounge room. But we put on thermal and fleece jumpers BEFORE we even think about turning on the heater. It has to be 15deg C or less before the heater goes on.

So somewhere between my usage and yours will be a 'zone' that you can reach that will both use less power and still provide optimum comfort. Note, optimum, not maximum.

That is what's costing you, friend!

Posted Tuesday 31 Aug 2010 @ 7:21:07 am from IP #
Anonymous
Unregistered

Hey!!!
I read your post and I think that you should some how reduce your cost otherwise you could suffer from it later and in my opinion resources should be used in effective way to reduce consumption. Effective use of resources will lead to betterment in future.

Posted Tuesday 31 Aug 2010 @ 8:26:35 am from IP #
dave lawrence
Member

yes I agree with the two posts above.
look at everything you use and see if you can do without it or use it differently (more efficiently). the easiest and cheapest way to save power and water (and $$$ ) is by modifying user behaviour.

Posted Tuesday 31 Aug 2010 @ 8:34:31 am from IP #
Bearamundi
Member

I think someone here may have already used a good metaphor which bears repeating anyway. Your situation is like putting a fridge (your built environment) inside an oven (your home) and running the fridge using sustainable tech solar panels. Result, ongoing unsustainability.
The person you are helping is the CEO of your Energy provider and his Christmas Bonus.

Posted Tuesday 31 Aug 2010 @ 10:12:03 am from IP #
Bearamundi
Member

Sorry, there should be 4 fridges in the oven for the metaphor to hold...

Posted Tuesday 31 Aug 2010 @ 10:44:49 am from IP #
swanning_it
Member

I'm wondering Warren, if you haven't mistaken your solar capacity.

You mention the $3k you paid and incentives of about $7k being a total installed price of about $10k a year ago. That sounds a lot like a 1kW or perhaps a 1.5kw system rather than a 3kw system to me.

I might also add that electricity prices in Qld (sounds like you're a Qld resident by the tariff) went up by 15%, which has to also be included in your savings!
Ian

Posted Tuesday 31 Aug 2010 @ 8:46:43 pm from IP #
rockabye
Member

Sounds like you are still winning Warren. You have probably added a significant figure to your house value and your getting it paid for as well.

Now you have moved your roof into the 21st century you need to do an energy audit of your energy use to catch up downstairs. Power use is always interesting to investigate. For some it's a bit like buying a brand new car and driving with flat tyres and the handbrake is still on. Once you find out what is using all that power you can do something about it.

To measure each household item,and if in Qld, you may be able to get the Climate Smart wireless energy meter installed for $50 to help. The ATA also sells a very accurate Powermate Lite plug in meter for about $120 to measure individual appliances. I have both and they a very handy.

Posted Wednesday 1 Sep 2010 @ 12:31:28 am from IP #
wmeg
Member

Thanks for all of the replies.
It is not quite like I have all four a/c units going at once. Where I live is more like a compound with
1.studio (4.8x3.2) which is fully insulated and has trees on 2 sides and has fan and vent windows.
2.my wife's (4x3.2) office which again has fan vent windows and is fully insulated
3.shed with my office (4x3.2) which is fully insulated and has fan.
4.cottage which is 7.2m x7.2m and has ceiling insulation, whirly birds,6 ceiling fans and also blanket under the tin plants growing up the northern side and verandahs on the western,southern and eastern side.
I have large trees on my Western boundary.
After it hits 35 degrees 100% humidity all bets are off.
I would be interested to learn if there is anything more I can do in mitigating the furnace like conditions of Qld.

Warren

Posted Thursday 2 Sep 2010 @ 8:03:20 am from IP #
cool at home
Member

How much of your insulation is reflective? If you can't top that up, perhaps reflective roof paint would help?? Really need reflective insulation more than batts in Qld.

Heat and high humidity are a bugger to deal with - if you can find a low cost answer to that one, you'll be rich!

Also, I noted Swanning_it's comment re the size of your system... we paid $11K for 3.24kW system earlier this year, which I think was a pretty 'standard' price. A year ago RECs were lower and the price was higher. $3K out of pocket definately sounds more like a 1.5KW system than a 3. Check what you've got...

Good luck

Posted Thursday 2 Sep 2010 @ 8:14:41 am from IP #
Bearamundi
Member

Warren, Ok so we have 3.5 fridges in the oven, on which the sun is beating down. (I hope you are smiling 'cos a bit of lightness never hurt anyone). I can sort of see your problem, that you have separate buildings all with the same need, so you kind of have to double up on everything. Could some buildings be amalgamated?
I personally would treat humidity and temperature separately. It is bad for your health to live in high humidity (50% is more or less the ideal). Do your a/c units have a de-humidification function? I'd install a temp/humid sensor (ebay for $35) and get your humidity into that range no matter the cost (no point in being the richest man in the graveyard).
Then I'd go to work on the temperature. It might mean a massively insulated fly-roof over some smaller buildings, I'd eliminate solar radiant gain. Maybe some kind of deep earth hydronic cooling system working off a heat-pump, I'm out of my depth here.
I'm in Newcastle and I have stuck at passive cooling techniques and can honestly say we enjoy year round comfort without a/c. House might get hotter than 25 degrees once or twice a summer but I'm working on that too. Good luck....

Posted Thursday 2 Sep 2010 @ 10:35:41 am from IP #
Bearamundi
Member

Warren, I found a cheap possible answer for you in Silverbatts (Australian Reflective Insulation). They have an R15 rating and study indicates they totally eliminate heat gain through the roof. $175 for 32 batts, a simple ingenious design. I'm definitely going to get some.

Posted Friday 10 Sep 2010 @ 10:46:55 am from IP #
ghostgum
Member

Single layer foil insulation is usually about R3 in the downwards direction, and R1 upwards. As you go above this, you may find that the dominant heat gain is then through your windows, not the roof. So it may not be worth going to R15.

Posted Friday 10 Sep 2010 @ 12:57:41 pm from IP #
Bearamundi
Member

Hi Ghostgum, R15 is such a huge barrier though don't you think? And the price is amazing as well.You could forget about forced roof space ventilation altogether. I think they are a stunning but poorly marketed product. I've never seen anything else that comes close. They just slide apart so access to roof is easier than single foil.
what do you reckon about taping Bunnings plastic around the windows? That's all I do, not the most appealing visually but i've done it on windows we don't use a lot.

Posted Friday 10 Sep 2010 @ 1:13:19 pm from IP #
LanceTurner
Key Master

You might want to recheck that rating, R15 sems way too high to me. There are two systems, the one we use here in Oz (and much of the rest of the world) and the US system. To convert from one to the other you divide the US system by 5 or so (5.1 or 5.4, can't remember now). So in fact that R15 is probably less than R3 in real terms...

Posted Saturday 11 Sep 2010 @ 2:28:24 am from IP #
LanceTurner
Key Master

Ok, more info at http://www.silverbatts.com/page15.html

Seems the 'Equivalent R value' can be up to 15, but it's different for each installation. The real value is around 4...

Posted Saturday 11 Sep 2010 @ 2:32:29 am from IP #
Sunshine
Member

wmeg,
If you have Tariff 33 and solar panels that is the way to go, as your export of solar to grid is not affected by tariff 33 consumption. Tariff 11 and other tariffs, consumption will however reduce your export to grid.
Are you sure you have 3kW system, $3000 out of pocket expense sounds more like a 1-1.5kW system to me?
I have 3kW system, with 3 air conditioners (on Tariff 11), and pool equipment on tariff 33 and my bill shows a credit each quarter of around the $300 mark.

Posted Saturday 11 Sep 2010 @ 12:36:35 pm from IP #
Bearamundi
Member

I'm not sure you are right Lance, but you sound it. I read a test somewhere on these batts and they apparently "totally eliminated" heat gain through ceiling. I'll try to find it.

Posted Saturday 11 Sep 2010 @ 1:21:15 pm from IP #
Bearamundi
Member

The rating given here is R6, more in the ballpark: still relatively impressive for the price don't you think?

http://www.goingsolar.com.au/pdf/catalogue/GS_21_insulation.pdf

Posted Saturday 11 Sep 2010 @ 1:28:53 pm from IP #

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