# Forum Home Renovation Solar Electrical Systems  changing to solar?

## allyrabbit

Seems to be lots of advertising about changing over to solar, before the Government rebate runs out... 
Has anyone done it?
How much did it cost?
Is it cost effective and cheaper? 
Our power costs have been rising considerably in the past year, and even though we used LESS power in our last quarterly bill, our bill was $100 more! 
Looking at ways to reduce our usage. We already have a timer in our shower (3 1/2 mins)... turn lights off when not in a room, currently too scared to turn on our heat pumps as it is still only March. 
Looking at upgrading ceiling insulation, and putting in insulation under the wooden floors throughout the house. Have put in wall insulation in kitchen/laundry and bathroom that I have renovated, but the rest of the house has NO wall insulation at all. Outside of house is vertical weatherboard, and most walls inside have dado up to my head height... 
Any suggestions/advice gratefully received, thanks,
ally  :Biggrin:

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## johnc

Improving the efficiency of the home gives most bang for the buck. Insulation and draft control being the best to concentrate on, then solar hot water, then appliances, then lighting, then solar panels. When the rebate drops they will get more expensive but the systems like all goods come down in price overtime as production efficiencies and new products come on line. It is only a matter of time before they drop back to their current pricing. 
I wouldn't rush in unless you are dead keen on a 1.5kw system at current prices, look at feed in tarrif as well. If you are not home during the day they work, but if you are it probably isn't worth the effort for the smaller systems.

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## allyrabbit

thanks Johnc, 
none of us are usually home during the day... except for around 3 months of the year... school hols. 
Have looked at the tarriff that my state will pay, and it is only 20c per KW, whilst most other states in Aus are like 44c..... 
Not in a desperate hurry, but worrying about paying our power bill, when we have just been told that it will have gone up over 100% in the next 5 years!!!! Yet, my pay won't increase that much.. how are we meant to survive? 
Working on the insulation currently... and draft control. Need to place blinds on kitchen and laundry windows to stop heat from escaping! 
Does anyone know when the Fed Govt rebate stops? Seems to be the carrot used in current advertising, to get in before it stops....

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## johnc

June 30th, but it reduces it doesn't end completely. The amount of power saving on a small system can probably be at least matched in dollar terms by the changes you are proposing. It is something you really have to do your homework on, it differs per house and per household, depending on a wide range of factors the main one being household energy leakage through poor design and poor use.

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## Bloss

Solar what? PV? or Solar hot water? I am a great supporter of renewable energy, but Tasmania is a sub-optimal place for current solar PV technology. That might change in a few short years and in the mean time you pay dearly for being an early adopter. 
The cheapest energy is the energy you don't use! So as other have said you are better to do some more of those things to and around you houses you have already started to do before you move to a solar PV array in Tasmania even with the Fed subsidy. As johnc says - no great advantage to rush. 
I assume your heat pump reference is to reverse cycle for heating? Again their performance drops dramatically below 10 degrees for most designs available in Australia. Have a look here for some more ideas: http://www.yourhome.gov.au/technical/fs41.html

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## Smurf

The bottom line is that a 1.5kW system installed at a good site (no shadows and facing north) in Hobart will reduce your electricity bills by approximtely $420 per year. 
When you are home, how much power you use etc has no real effect on this. Put up a properly working 1.5kW system on your roof in Hobart and you pay $420 each year less for electricity than you otherwise would have. 
Now, I will acknowledge that saving $420 a year isn't going to make you rich, but it can still be worthwhile depending on what you pay for the system and considering that this saving will steadily increase in line with the price of electricity (which goes up AGAIN soon by the way, I forget the precise figure but it's over 8% from memory on or about the 1st of July this year, then another big rise on top of that 12 months later is already planned and publicly announced).  
So it would be fair to say that the $420 would be closer to $500 a year 18 months from now. Given that you can get these systems from under $2500 fully installed, it seems like a reasonable deal to me if you can afford the $2500.

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## johnc

You only feed back into the grid the surplus power the home doesn't use. So if you are at home during the day with everything running there will be less or nothing going back in.

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## ringtail

Why is everyone so hung up on feeding back into the grid and not stand alone systems ? Sure the cost is pricey with batteries and inverters but thinking longterm, which is the only way to think with these things, it must be better. It costs bugger all to stay connected to the grid and use nothing. Or maybe get tricky and do both. Once your batteries are fully charged then feed back into the grid. I dont know much about solar ( 0 ) but the way pricing is going and Bob Browns B--ch carbon tax, can we afford not to look at stand alone systems with the same vigour as feed in ?

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## Bloss

> You only feed back into the grid the surplus power the home doesn't use. So if you are at home during the day with everything running there will be less or nothing going back in.

  No that's not how it works: _All the power produced_ is fed back into the grid. 
You are confusing how one gets paid for the power rather than what happens to the actual energy produced. How one gets paid and how much varies across all States & Territories. Whether you are using or not using power at home all the power coming off the solar PV array is being fed into the electricity grid and being metered. 
In Tasmania there is a net feed-in tariff (FiT) of 20c kW/h. The way that works is that the amount of power you use in kWhrs is netted against the amount of power generated from your solar power PV array (again in kWhrs) and you get paid 20c/kWh for that difference. 
So for most people who are average power users (ie uses around 8500 to 9500 kWh a year) they would never get paid a FiT for the solar power as they would be using more than they generate. But - the solar generated power offsets your power usage so you pay only for the net amount used at whatever is the rate you are on. 
For example, if you have a 1.5kW system on your roof that would be on average produce about 1800kWh [eedited - to correct error pointed out by Smurf below) a year (it will vary on your location and year by year but roughly that over time as each kW in Hobart will give around 1200kWh annually). If you pay on average 20c kWh (around the middle price in Tassie I think) your revenue from a 1 kW PV system will be around $240 a year for a 1.5kW system about $360. At that rate of return you will barely have paid off your system after 15 years or so - more if you count the cost of the money (ie: what you might have received if you simply invested it safely at say 6%). 
In summary - Tassie is not a great place for PV because of its latitude and lower solar insolation/ irradience levels (sunlight hours and the intensity of the energy form the sun per m2). The upside might be a hedge against the inevitability of rising power prices from fossil fuels, but with the price os solar systems going down around 20% a year (ignoring the various subsidies) you are best to wait and see in regards to PV, while doing the various other things that really do save energy and money and help the environment. 
The story will be different in every State!

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## Bloss

> Why is everyone so hung up on feeding back into the grid and not stand alone systems ? Sure the cost is pricey with batteries and inverters but thinking longterm, which is the only way to think with these things, it must be better. It costs bugger all to stay connected to the grid and use nothing. Or maybe get tricky and do both. Once your batteries are fully charged then feed back into the grid. I dont know much about solar ( 0 ) but the way pricing is going and Bob Browns B--ch carbon tax, can we afford not to look at stand alone systems with the same vigour as feed in ?

  The numbers do not stack up for standalone systems - not even close - _unless_ you are at a remote site and therefore rely on fossil fuel generation for your energy needs. If you use diesel (or even bottled gas) for power generation and have no grid access then it is already competitive to use solar PV. But - with the feds no longer supporting remote area systems few can afford the capital cost to put in a new system (gensets etc have usually already been paid off!). Solar has high capital cost and then no fuel costs just some occasional maintenance - but batteries need regular replacement as do inverters (although these now can last 10, 15 or even 20 years). 
The grid provides security of supply - something that those connected to it take for granted, even if they are in areas where the infrastructure is such that blackouts or brownouts are common. In towns and cities especially we expect to be able to have our electricity (and gas too if we are on the gas grid) 24/7 and with rare interruption. Batteries work, but are expensive and need maintenance and replacement and if you talk to anyone not on-grid you will find that their whole way of ding things is changed by that fact. Better than no power by far, but like those who live off tank water - always highly aware of the risks posed by the lack of security and resilience. 
The future grid will look much different as it is already being re-designed and configured to allow many generation types and locations (solar, wind, hydro, geothermal, more gas as well as existing coal generators for many more years yet). This is referred to as an Intelligent Distributed Grid - anyone who wants some more info on that can read here: Intelligent Grid Report: a value proposition for distributed energy in Australia (Publication - Technical) - much of the work described there is already underway. 
it is fine to think long term, but moving early only gives an advantage in a few cases or if there are other reasons that make it sensible. In this case a gross feed-in tariff (subsidy) such as was in NSW (it was 60c now 20c - better than net, but pretty poor) and is now in ACT, or if your power supply company offers you a long term contract to buy your output at a fixed price for a fixed period (10 years as some in Qld are) might make the investment numbers work for grid connected. They rarely do otherwise and waiting and using energy efficiency measures (and solar HWS) make more sense and building a standalone system when you have grid access doesn't now and probably never will.

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## SilentButDeadly

The latest issue of Choice mag had un update on the pay back time for a 1.5kW grid connect PV system in each State....in Tas it was 20 years.   
Personally, I'd put your money into making your use of electricity as efficient as possible especially in terms of heating water or house or cooling food or house.  Much better bang for buck.

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## ringtail

Why is everyone so hung up on feeding back into the grid and not stand alone systems ? Sure the cost is pricey with batteries and inverters but thinking longterm, which is the only way to think with these things, it must be better. It costs bugger all to stay connected to the grid and use nothing. Or maybe get tricky and do both. Once your batteries are fully charged then feed back into the grid. I dont know much about solar ( 0 ) but the way pricing is going and Bob Browns B--ch carbon tax, can we afford not to look at stand alone systems with the same vigour as feed in ?

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## Bloss

> The latest issue of Choice mag had un update on the pay back time for a 1.5kW grid connect PV system in each State....in Tas it was 20 years.

  The figures used by Choice have been questioned, but see above - Tassie is sub-optimal for solar - unless power prices jump dramatically (in which case the operation of PV is still sub-optimal for current technology, but the revenue level might justify it).   

> Personally, I'd put your money into making your use of electricity as efficient as possible especially in terms of heating water or house or cooling food or house.  Much better bang for buck.

  Yep - if you are in a place with a gross FiT (the ACT is the only one worth it right now) then do this stuff first then think about PV.

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## johnc

> Why is everyone so hung up on feeding back into the grid and not stand alone systems ? Sure the cost is pricey with batteries and inverters but thinking longterm, which is the only way to think with these things, it must be better. It costs bugger all to stay connected to the grid and use nothing. Or maybe get tricky and do both. Once your batteries are fully charged then feed back into the grid. I dont know much about solar ( 0 ) but the way pricing is going and Bob Browns B--ch carbon tax, can we afford not to look at stand alone systems with the same vigour as feed in ?

  I don't think you are allowed to use a battery base system as a feed back to the grid. Something to do with not returning power when the grid is shut down.

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## Danny

Given that the O.P. is from Hobart, I am going to ask something that I have wondered about and hope I don't look foolish in doing so!!! 
The link at bottom shows that Hobart has a low average of 5.9 hours of sunshine per day when compared to Sydney 6.8, Brisbane 7.5, Canberra 7.6, Perth 8.1 and Darwin 8.5. However, Melbourne's average is only 5.7. 
I have often read that Hobart's climate is not particularly suited to PV but have never seen Melbourne's suitability questioned. Given that (as per what else I have read) efficiency falls away once ambient temperatures exceed 26 degrees and that Melbourne experiences higher summer temperatures than Hobart, why isn't Melbourne considered the Pariah for solar power generation given the less available sunshine and the hotter temperatures? 
I have also never read about efficiencies falling away below a certain temperature. Do they? Given that satellites successfully use small solar panels to generate power and that Hobart's average temperature is only a few degrees less than Melbourne's, to what degree (excuse the pun) would this be a factor? 
Bloss' reference to Hobart's insolation is obviously a factor but how much of a % difference does this make? Also, if insolation for both cities was magically the same (for the sake of arguement) but the other factors mentioned all kept the status quo, would Hobart provide greater efficiency than Melbourne?  The Great Australian Weather Debate

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## Smurf

> You only feed back into the grid the surplus power the home doesn't use. So if you are at home during the day with everything running there will be less or nothing going back in.

  A valid point yes, but in the context of the OP who is located in Hobart it has zero practical effect. A 1.5kW system in Hobart will save about $420 a year regardless of where the power ends up.

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## Smurf

> So for most people who are average power users (ie uses around 8500 to 9500 kWh a year) they would never get paid a FiT for the solar power as they would be using more than they generate. But - the solar generated power offsets your power usage so you pay only for the net amount used at whatever is the rate you are on.

  Unless the household has a continuous load running all day which exceeds the maximum output of the PV system then there will be times that export to the grid does occur even though the house remains a net importer.   

> For example, if you have a 1.5kW system on your roof that would be on average produce about 1200kWh a year (it will vary on your location and year by year but roughly that over time).

  I would suggest that a minimum of 1800 kWh should be expected for a properly located and working 1.5kW system in Hobart. My 1.0kW system produced 1335 kWh in its first 12 months (22 degree pitch, facing 20 degrees West of true North).  
Overall, in Tas space heating is the obvious point to start with when it comes to saving energy and I'd guess that 80%+ of all privately owned households would have at least given it some thought. I'd say that the majority of homes more than 15 years old would have changed heating fuel at some point - it's not like Victoria where everyone just puts in mains gas and leaves it. With the potential cost variations so great between different systems, heating is something worth giving some thought to here in Tas. It's also been a fairly political subject over the years, another thing that would presumably have prompted people to give it some thought. 
Once the heating is right, then it's time to worry about the rest. :Smilie:

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## Bloss

> Unless the household has a continuous load running all day which exceeds the maximum output of the PV system then there will be times that export to the grid does occur even though the house remains a net importer. 
> I would suggest that a minimum of 1800 kWh should be expected for a properly located and working 1.5kW system in Hobart. My 1.0kW system produced 1335 kWh in its first 12 months (22 degree pitch, facing 20 degrees West of true North).

  What happens on any particular day is pretty much irrelevant - its what happens on average over the year(s). I wasn't suggesting that at some times there was not going to be an excess of output to grid over input drawn from the grid - simply that on average that you won't. It what you get over the life of the system that counts. 
Apologies - the ~1200 kWh I mentioned was an average for each 1kW capacity so over time a 1.5kW system will give around 1800kWh annually as you say - my mistake. 
In Hobart panels should be angled at around 40-45  degrees to get optimal output, but as with the West orientation on your system it is not a great difference in over all output over time as the greatest output is when the sun is highest in the sky each day regardless of time of year. Melbourne is not much better than Hobart either as you say.

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## ringtail

Mmm, sorry for the double post earlier. Thanks for the education bloss. Like I said, I know nothing about solar. Ive got a mate building a new house up at Yandina ( sunny coast) and he is going stand alone with solar and wind. Last visit he showed me his generator room, which made me chuckle a bit. But I will be keeping a very close eye on how it goes.

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## Bloss

The technologies involved work exceptionally well - it's simply about cost at present. If there is a massive spike in prices then the number would change. Like Tassie - it will still work - as it works in northern Europe, but we still pay really low prices for power (even though we think we don't!) so it's that relative comparison of prices that is the issue. There are improvements in batteries coming that will be game changing and wind and micro-hydro to are improving greatly too - so it won't be too long and there will be off-grid options to think about. Many might choose to use the grid pretty as  their back-up - will pay a connection/ access fee only 'just in case'.

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## Smurf

> What happens on any particular day is pretty much irrelevant - its what happens on average over the year(s). I wasn't suggesting that at some times there was not going to be an excess of output to grid over input drawn from the grid - simply that on average that you won't. It what you get over the life of the system that counts.

  Agreed, though my real point is that in Hobart it is irrelevant whether any or all of the power is exported to the grid since it has the exact same value either way. That is, the import and export rates are identical in Tas for systems under 3kW.  
So the finanical benefit of installing a grid connected system in Tas is simply the annual power output multiplied by the rate per kWh - whether you use it within the house or it is exported to the grid has no practical effect. If you use it then that's power you would otherwise have paid for. If it's exported then you are credited for it at the exact same rate. Six of one, half a dozen of the other. 
The relevant electricity tariffs in Tas are Tariff 31 and Tariff 110. Details of this and other tariffs as follows: 
Tariff 31 - 22.648 cents per kWh. This rate is for any purpose (residential) not covered by another (cheaper) tariff.  
Tariff 110 - 22.648 cents per kWh. Residential solar grid connect export to grid (systems up to 3kW). 
Tariff 42 - 13.659 cents per kWh. This rate is 24 hour supply for hard wired space heating and continuous (NOT instantaneous) storage hot water systems (including heat pump and solar boosting). This tariff is very commonly known by the marketing name of "HydroHeat" (pronounced as two words). 
Tariff 61 - 10.997c per kWh. Off-peak on for two periods each day (night and afternoon).  
Tariff 62 - 10.357c per kWh. Off-peak night only.  
These are the rates charged by Aurora Energy which is the only retailer supplying household customers with electricity in Tasmania.

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## terenjac

Everyone seems to be talking about solar power.  How about wind power?    No, I don't mean those enormous towers you see on coastal wind farms.   I live on 2.5 acres with my nearest neighbour 1 km away and the nearest town 15 km away.    So why not a small wind generator just for my home ?    
It would work at night (if the wind was blowing) and the neighbour(s) would not see or hear it. 
Has any work been done comparing solar with wind power for an individual home ?

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## SilentButDeadly

The ATA has done a bit of work in this regard and a re a ....it is worth it if you have the right wind conditions.... Alternative Technology Association website

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## SilentButDeadly

> I don't think you are allowed to use a battery base system as a feed back to the grid. Something to do with not returning power when the grid is shut down.

  You can use a battery based system in a grid feed situation but you need a different inverter/controller to one you would normally find in a grid connect system.  A couple of brands make them. Selectronics (an Oz company) comes to mind.  They are much more expensive (up to double) that a typical equivalent inverter due to the extra widgetry and the like.....add to that the spectacular cost of energy storage and you'd have to really want to do this...  
...but it is what I'd do.  After I made sure our use of sparks was at its most efficient.

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## Bloss

Wind is again not yet cost effective in most places - and also whether you are looking at on-grid or off-grid. In an off-grid system adding a wind turbine can make a lot of sense and be cost effective. It allows generation at all hours and all weather (and at night of course when in many places wind speed and consistency is higher) so maintaining batteries at a good charge and a good complementary generator to PV. 
On-grid is mostly a cost issue. In the ACT for example you can get a FiT payment for wind generation the same as for solar PV, but a 1kW wind turbine will cost you around $5-6,000 just for the turbine and a standard mount. You need to add on the inverter cost and connection charges, who knows what mounting system or tower, full building and development approval costs - mostly adding up to around $20,000 which would never give you a payback. For that amount you can buy and have installed (if you have the right roof) a 4-5kW PV system. 
The output for wind turbines on average is not great - wind turbines need minimum speeds and as consistent a flow as is possible. We often think of places as 'being windy', but when one looks at the wind maps (publicly available) for Australia there are fewer optimal areas than one might think. On the coast of course are the best sites, but even then local topography can make huge differences. When one moves into urban areas the issues become even more complicated. This ATA report for the Victorian government is about Melbourne, but the issues raised apply to all urban areas at some level: http://www.advocacypanel.com.au/docu...neviablity.pdf  
If you are serious about the environment so far as you power use goes then reduce first (though energy efficiency practices and changes to your buildings - shading, insulation, hot water, better heating especially in cool climates) then buy GreenPower at some level. I buy 200% GreenPower, but also have PV, but that's because in the ACT makes economic sense to do so if you can afford it. 
The issues for small scale wind are similar to large scale and PV - intermittency of supply. That's a big problem _if_ you have a single source and location for power generation (such as one residence at the extreme), but is not an issue if you have a smart grid and can locate wind and PV and geothermal and wave and other renewable technologies across a large geographic area. The variability of single types of generation and locations effectively disappears in that situation as there is continuity of supply to the grid. Add in storage using such technologies as molten salt and pumped hydro (only Australians think these are novel - the rest of the world is building them!) and end-users will see no difference to the way they use electricity now. The intelligent grid also allows demand side management - basically unused in Australia right now. 
Energy efficiency to reduce demand will be critical. We have had energy so cheap we see no problem with using it wastefully - I just think that's really dumb. We all have seen the results in our tools - my Dah had electrical tools made in the '30s and 40s that he used in his business as a builder into the 21st Century. Some without anything except lubrication and motor brushes etc ie: the design allowed for refurbishment and then continued re-use. We will need to return to that philosophy rather than the continuation of the throwaway mentality we adopt because of the cheap chinese tools. I think we will see the return of many many small business and a revival of old skills as we seek to refurbish and re-use - a return to quality and craftsmanship because in the long run it is better.

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## Smurf

> The issues for small scale wind are similar to large scale and PV - intermittency of supply. That's a big problem _if_ you have a single source and location for power generation (such as one residence at the extreme), but is not an issue if you have a smart grid and can locate wind and PV and geothermal and wave and other renewable technologies across a large geographic area. The variability of single types of generation and locations effectively disappears in that situation as there is continuity of supply to the grid. Add in storage using such technologies as molten salt and pumped hydro (only Australians think these are novel - the rest of the world is building them!) and end-users will see no difference to the way they use electricity now. The intelligent grid also allows demand side management - basically unused in Australia right now.

  Agreed. If we're going to make a major transition to renewable energy at reasonable cost whilst maintaining reliablity then it's going to be through the grid, not by everyone having their own stand alone power systems.

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## johnc

Another ermerging technology is ceramic fuel cells, such as the blu-gen units that use natural gas to produce both electricity and hot water as a by product. Although not an alternative renewable they do offer very effective conversion rates of gas to power and are currently being trialled both here and in Europe. At this stage they are still expensive at around $40,000 per household if they take off economies of scale will drop the price substantially.  germany remains interesting raising solar power to 1% of needs by 2009 and 25 by 2010, eventually they will overtake nuclear as a contribution to total power produced and it is expected that continueing efficencies will drop the installed price per KW to below any current alternative and probably with-in 10 years.

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## Bloss

> Another ermerging technology is ceramic fuel cells, such as the blu-gen units that use natural gas to produce both electricity and hot water as a by product. Although not an alternative renewable they do offer very effective conversion rates of gas to power and are currently being trialled both here and in Europe.

  Yep - I mentioned them in a post last year: http://www.renovateforum.com/f193/hi...riences-88729/ 
They will have a role, but in the end they use natural gas (albeit very efficiently) so are not renewable as you say. But I think they might head to an eventual use of biogas sourced renewably from algae and similar, but who knows.

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## johnc

> Yep - I mentioned them in a post last year: http://www.renovateforum.com/f193/hi...riences-88729/ 
> They will have a role, but in the end they use natural gas (albeit very efficiently) so are not renewable as you say. But I think they might head to an eventual use of biogas sourced renewably from algae and similar, but who knows.

  I am inclined to agree, even the Gippsland Water Factory produces about a third of its hefty power needs from gas collected from effluent treatment with-in its own plant. It would seem possible that we can make far better use of what we have, reducing waste and producing power at the same time. The water factory when it is fully functional should be able to make compost from what was once a septic sludge. Not all waste will be usable but there will be a lot less produced. If we hooked onto this idea we would have been producing drinking water from Weribee in Victoria using a fraction of the power it is going to take to produce water from the sea. Not only that the plant would have been generating some power from its own process rather than 100% off the grid.

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## allyrabbit

thanks everyone for their replies. Since posting, I have received some quotes for a solar system linked to the grid here in Hobart... cost is between $3500-$4000. If it is going to take like 20 years to come out positively financially, then it is not worth having. Definitely not rushing into it. 
Considering investigating solar hot water.. have no idea of the cost. And am buying insulation batts this week for the roof space. 
And yes I was referring to a reverse cycle air conditioner, although I have NEVER used it for cooling... only for heating purposes. And although we have had cold days already, have resisted the urge to put it on...

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## johnc

We went down the solar HWS path, not sure the cost now but about three years ago it was under $1,000 but we had to upgrade the gas line to 1" which we did know beforehand.

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## Smurf

> thanks everyone for their replies. Since posting, I have received some quotes for a solar system linked to the grid here in Hobart... cost is between $3500-$4000. If it is going to take like 20 years to come out positively financially, then it is not worth having. Definitely not rushing into it. 
> Considering investigating solar hot water.. have no idea of the cost. And am buying insulation batts this week for the roof space.

  I keep hearing this "20 years to break even" but I've never seen the calculations behind it. Even if you paid $4000 and electricity prices were unchanged over the coming years, it's still only 8 years unless you are charging yourself interest on the money invested in solar (which is not unreasonable, but I doubt that the average person would factor this into their calculations). 
For me, solar is basically a hedge against inflation. Spend some $ now and produce 1800 kWh a year on an ongoing basis. How much that power will be worth is anyone's guess, but I'd be very surprised if prices didn't keep rising at least to some extent. 
Hot water - worth looking at but in most cases I've seen the economics of replacing a working HWS with a solar one are at best break even with that of installing a PV (solar electricity) system instead. Yes the HWS saves a bit more power if you are a moderate to high hot water user, but the power being saved is charged a a lower rate. Still worth looking at however - cost is very site (house) specific so get quotes. 
Insulation - good idea there. Anyone in Tas who doesn't at least have ceiling insulation would be well advised to get it regardless of what form of heating they have.

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## Bloss

> I keep hearing this "20 years to break even" but I've never seen the calculations behind it.

  The calculations are no different to any investment so can be done using the standard investment template that comes with all spreadsheets. You are right that few people think that way, but IMO they should and just because one does not want to count interest foregone that calculation should be included before spending money. That is especially so if one is trying to 'do the right thing' as you can have a much bigger bang for your buck spending on other things than PV. 
If one spends say $4000 and locks it up in an asset then the calculation of the return on the investment (ROI) has to include not simply the revenue from the asset and deduct the depreciation on the asset over a suitable period (as at the end the asset will stop earning money and in the meantime it will need at least some maintenance such as a replacement inverter), but also take into account the opportunity cost ie: what alternative investment option might the capital have otherwise been invested in - for example a fixed interest bank deposit with accruing compound interest at a long term rate - say 6%. 
If the asset investment gives a higher estimated return than that 'safe' investment then it would be the one to go for, if not then you are better off investing in something else. In the ACT with a gross feed-in tariff it is a no brainer (if you have the capital of course - in fact you can make a good case for extending a mortgage to buy a solar PV system and still make a solid ROI). In Tassie I reckon that would be a tough call. 
But - the real world experience, after PV panels having now been in place for more than 40 years and at scale for more than ten years in Europe, suggests that the panels are likely to still be producing solid output at 30 and 40 years not simply the 20-25 years that warranties imply. When you add 5-15 years to the revenue side then the ROI can look better. And as you say as prices go up then you will be doing even better. My argument is not against solar PV - I love it - but more that unless you are getting support from a FiT to be an early adopter (and right now that really means the ACT only ) you will gain by waiting to move.

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## Wilesy

I thought I would just add my experience to this debate as I have a 3.2 kilowatt system installed on my Mancave rather than on my house, it cost me just under $11,000 at the time, and it has been a year now and each and every bill has been reduced to a zero balance and them owing me about $200 each time.  Our average electricity bill is about $500-$600 depending on the season and so far in the last year I have paid nothing and just keep banking the $200 cheque each time.  Mine is connected to it’s own meter which records the electricity made and it’s deducted from the meter which uses electricity.  Looking at my last bill in front of me, it says I made $772.40 from the panels installed, the bill was $579.18 and the difference is that they owed me was $193.22 which will be direct deposited into my home loan account.  Having said that, our tariff that they pay me is $.60 per kilowatt hour and I only pay $.19 per kilowatt hour of usage. That payback was only for those quick enough to get it installed in the early days.   According to our inverter, it tells you all the information it collects for example, the total hours metered in one day, total since it was originally turned on, how many hours it has collected power per day, how many kilowatts it produces per hour etc, etc.   It’s pretty good, we average 14-15 kilowatts most days, I have seen it go as high as 21 kilowatts in one day as ours are positioned pretty much due north. Positioning of the panels really makes a difference in power created.  So, in other words they pay me in average $8.50 - $9.00 per day, every day 7 days a week, sometimes more, sometimes less but it all averages out. Depending on your views, I don't really like them on the house, so I opted for installing them on my mancave and it doesn't look too bad.

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## ringtail

Man cave ????? That aint a man cave Wilesy thats a mansion posing as a shed :Biggrin:  So what are these " massive " costs with storage for standalone systems. I can buy high quality deep cycle batteries for $ 120. I can buy near new deep cycle batteries for half that. On a good day I can get 1 year old deep cycles fo free. Whats the problem ? How many batteries are you meant to have. I dont know much about AC power but I know lots about 12 volt DC. Battery storage - inverter 12 v in 240 ac out. Mmmmm, I wonder how long I could run my welder for.

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## Wilesy

> Man cave ????? That aint a man cave Wilesy thats a mansion posing as a shed .

  Yeah, I know, I am pretty proud of it, this forum seems to be where I belong, a mancave with a budget of $70k ended up costing close to $500,000 by the time I finished.....now  I am on to the house God help me!!! Budget $650,000 which I have just about hit and the roof isn't even on yet....
Back on solar power, the Inverter does hum quite loudly but as the system switches off automatically at dusk it doesn't seem too much of a problem.

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## johnc

Most of us would have no wife and a feral bank manager to boot if we spent that much on a shed. Have you been given a certificate to say your are allowed near the bank balance again?

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## Wilesy

I promised not to argue about what she spends on the house  :Redface: $

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## Smurf

> Man cave ????? That aint a man cave Wilesy thats a mansion posing as a shed

  I thought you said you'd put some solar panels up, not that you'd built a factory to mass produce them.  :Biggrin:

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