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domwild
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Joined: 16/12/2005
Location: Australia
Posts: 873

Posted: 12:56pm 09 Apr 2014

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Hi,

RAC WA newsletter had an ad from Termico which claims a 26% return of a PV system. After first asking for the calculations unsuccessfully I contacted the RAC and then received the calculations from the company, which I reproduce here:

Cost of 1 unit of electricity on the Synergy A1 Tarrif = 0.26 cents
A 1.6 kw system will generate approximately 7.42 units per day.
This equates to $ 0.26 x 7.42 units = $ 1.92 per day.
Average annual production is 365 x $1.92 = $700.08.
Cost of a 1.6 kw system = $2190 .00 .
Return on investment is $700.08 divided by $2190.00 = 31.00%

Assumes you use all of the electricity inside the house. The 26 cents for WA is a little bit too high; no problem. The calc. assumes seven kWhs or four hours (?) of sunshine/day for each and every day of the year. There you can help me as this sounds a bit too optimistic.

If his calcs. are correct, then the system pays for itself in three years? Help!

Taxation as a means of achieving prosperity is like a man standing inside a bucket trying to lift himself up.

Winston Churchill

yahoo2

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Joined: 05/04/2011
Location: Australia
Posts: 1166

Posted: 12:08am 10 Apr 2014

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Hi Dom,

the generation figures are pretty close to the mark for Perth. Provided the panels are facing north, have no shading at any time of the day and are installed at an appropriate angle. I would expect you to average 3.4Kw/day in winter 7.4 in autumn and spring and 11 Kw in summer.

Your tariff is cheap compared to some eastern states rates, mine is 28 - 32 cents with an 18 cent J tariff.

The catch as I see it is your ability to use ALL the power generated during the peak hours of the day, presumably that is why the system is 1.6 Kw. To get the full benefit of the $700 of production you would need your existing usage to be substituting at least 900w every hour between 10.30 am and 4.30 pm from August through to the end of April.

There are wireless energy monitors that fit to the wires in your powerbox and you just sit the display on the bench in the kitchen that will tell you how much power you are using at any minute and some will chart usage through the day and tell you when you are using it.

Um what else. the 4.6 hours of solar per day is only a theoretical calculation. It says all the solar energy in an average day adds up to 4.6 hours at the systems max throughput in your case 1.6Kw.

The real cost of the install would be closer to $3000 but you would be letting the company redeem $1200 of Renewable energy credits in return for the reduced system price.

I'm confused, no wait... maybe I'm not...

domwild
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Joined: 16/12/2005
Location: Australia
Posts: 873

Posted: 12:13pm 10 Apr 2014

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Thanks, yahoo. The surplus would be fed back into the grid but new installations would not get $0.40/kWh as the feed-in tariff. The WA gov. tried to reduce this tariff but the political storm stopped the cut. I suspect the feed-in tariff would not be equal to the domestic WA tariff at the moment.

A friend told me his system saves him about $30/month, so lets call it 12x$30 or $400/year. His system cost $3,000, so we are looking at eight years payback time. I suspect the real payback figure for a solar PV system might be somewhere between the optimistic three years and ten years.

Taxation as a means of achieving prosperity is like a man standing inside a bucket trying to lift himself up.

Winston Churchill

domwild
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Joined: 16/12/2005
Location: Australia
Posts: 873

Posted: 12:29pm 10 Apr 2014

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Just read an article re EU and feed-in tariffs: They will be abolished. Every German consumer pays eu250/year more for the subsidies or eu20 billion. Exempt from the new EU-wide regulations are hydros up to 500 kW and wind systems up to 3 MW for the run time of the old feed-in tariffs, which is 13 years.

So the prescribed tariffs will be abolished and the providers will offer feed-in tariffs in a competitive market. The reason is the surplus of home-generated energy has brought the gas-powered generators into commercial difficulties.

The problem for the environment is the only way industry managed to compete then against wind/solar/biomass is by using more brown coal to generate cheaper electricity.

Industry is happy, environmentalists are not.

Taxation as a means of achieving prosperity is like a man standing inside a bucket trying to lift himself up.

Winston Churchill

norcold

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Joined: 06/02/2011
Location: Australia
Posts: 670

Posted: 01:57pm 10 Apr 2014

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You can get 40 cents feed in tariff, suspect your payback will be in lower end of your range. If you can afford it go for it. Subsidy days are over, the industry has had great support and once that support is stopped I feel, especially in solar the costs will drop and solar will shine.

Remove the greed and common sense will dictate the economic sensibility of RE, and help slow our crazy dependency on fossils. Truly believe we can have industry and the environment walking almost hand in hand. Never can it be perfect, but maybe sustainable, and that would be a great compromise.

We come from the land downunder.
Vic

yahoo2

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Joined: 05/04/2011
Location: Australia
Posts: 1166

Posted: 05:02pm 10 Apr 2014

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In SA the feed in tariff is gone.

At the moment there is a minimum retailer payment of 7.6 cents for new installs that will reduce to 6.0 cents with the cutting of the carbon reduction bill federally.

I think the WA f.i.t ended for new installs in 2011 some people got 40 cents the next group to the quota limit got 20 cents for 10 years.

The deals today are directly with the retailer (I think)

If you are running an A/C during the day from Nov to Feb you would probably get $300 of value in just 4 months (these are the months of the highest generation) That's 14% on your money just there, a self funded retiree here would say "better than twice bank interest, I'm in!"

I'm confused, no wait... maybe I'm not...

Downwind

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Joined: 09/09/2009
Location: Australia
Posts: 2333

Posted: 03:22am 11 Apr 2014

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The whole problem with solar is periods of oversupply and periods of over demand.
Until the energy suppliers can find a way to factor in screwing higher profit margins for a average household demand to offset the loss in general demand, than there will be zero return offered for a FIT.

Given time for industry to adjust, it will become more economical for solar, but of present their profit gain has taken a hit, and they need time to find a way to screw more dollars from the public to pay the executive bill.

Sometimes it just works

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