Just getting started on Solar HWS/Power investigations

[spudboy]

I've just read several 'Solar' threads here, and there seems to be some who say it's not worth it (95 year payback period for power :() but others say go for it. Anyway, I am thinking of getting something sorted before the rebates run out in June.

We currently have mains power, so the idea of feeding back into the grid and getting credits appeals, and I am sure having solar hot water will cut the power bill significantly.

Casting around the net I have found this offer for solar HWS and 1000W solar power for about $5.5K:
Adelaide Solar Power and Hot Water Special (http://www.energymatters.com.au/adelaidespecial/)

Does anyone know if the components listed are good quality?

Any other suggestions on who to contact? I had a look at SolaHart because they have been around for ages, but they only advertise HWS not power, and I think I'd prefer to have one company doing the whole lot.

Thanks
David

[NobbyTD5]

Origin Energy also install
originenergy.com.au/solar
bigger company - perhaps more protection agianst poor quality/installation
Nobby

[JDNSW]

I am not sure I would insist on getting the same company to do both - a bit like looking for someone who is both an electrician and a plumber - which is virtually what we are talking about!

John

[PhilipA]

and I am sure having solar hot water will cut the power bill significantly.
It is usually easy to check this by looking at your bill. HWS usually has a separate circuit and lower KW fee off peak 1 or 2.

If you are on off peak 2 which can top up the heating during the day , go back to off peak 1 which only heats at night.

My cost for 2 adults with 305 Litre HWS on off peak 1 at 5.3cents per KW hour was $13.67 for my last quarterly bill from Energy Australia. Usually it is a bit more but no more than $20 ever.

It will take a looong time top recoup the capital cost even with all the subsidies.
Maybe better to let it die before making the decision?
Regards Philip A

[spudboy]

Just checked my power bill for the last quarter.

I am being charged $0.0799 per kwh for my off peak HWS, which came to $55 of my bill. Not as much as I thought!!

So, ballpark, my HWS is costing about $250 a year to run, equivalent of about 3 tanks of diesel in the 110..... Pretty good value.

[vnx205]

That particular HWS needs good quality water and temps always above freezing.

[mcrover]

Our hotwater is on Natural gas and costs us around $300 a year.

Ive stopped looking into solar at the moment but 1000w is about a 1/4 of what I would want as a minimum to produce enough to offset our electric vehicals charging over night on off peak.

[PhilipA]

I always seem to be the Cassandra but i was just thinking of theimplications of this subsidy to buy solar for reinjection to the grid in SA detailed by Spudboy.

Some BOE calculations.

Say Normal power costs the distributor 10C per Kwh.( probably very generous)
The subsidy for injecting solar is 44c Kwh. and it appears from the offer that the 1Kw setup is designed only to inject power back into the system. No batteries are mentioned.

If 20% of power were produced by solar, then coal/solar power prices would have to rise by 60% to 16.8c kwh to compensate.

So you buy the 1Kw set up plus solar HWS for $5490

If you can generate 3kwh per day average summer /winter /sunny /dull then you get $9 per week or $450 per year, so you get payback in 7-8 years.
BUT , seeing you are selling it all back into the grid, you still have to use all the energy you are using now.

Now the more people taking up the option the more expensive electricity will come, so that at the end of the day you will pay 60% more for your power!!!

So say you pay $1000 per year now you will pay $1600.

So you gain $450 and lose $600.

BUT you feel really good about yourself for being a committed conservationist and are happy in the knowledge that all those who did not put solar on are paying much more.

Regards Philip A

[JDNSW]

I always seem to be the Cassandra but i was just thinking of theimplications of this subsidy to buy solar for reinjection to the grid in SA detailed by Spudboy.

Some BOE calculations.

Say Normal power costs the distributor 10C per Kwh.( probably very generous)
The subsidy for injecting solar is 44c Kwh. and it appears from the offer that the 1Kw setup is designed only to inject power back into the system. No batteries are mentioned.

If 20% of power were produced by solar, then coal/solar power prices would have to rise by 60% to 16.8c kwh to compensate.

So you buy the 1Kw set up plus solar HWS for $5490

If you can generate 3kwh per day average summer /winter /sunny /dull then you get $9 per week or $450 per year, so you get payback in 7-8 years.
BUT , seeing you are selling it all back into the grid, you still have to use all the energy you are using now.

Now the more people taking up the option the more expensive electricity will come, so that at the end of the day you will pay 60% more for your power!!!

So say you pay $1000 per year now you will pay $1600.

So you gain $450 and lose $600.

BUT you feel really good about yourself for being a committed conservationist and are happy in the knowledge that all those who did not put solar on are paying much more.

Regards Philip A

I think the problem with your calculation (and I have no idea how accurate the numbers you use are) is that the extra cost of the feed-in tariff is paid for at least in part by the extra charge made for renewable energy to consumers who elect to pay for it, and to this extent the increase in cost of coal fired power is not required. Also, if coal fired power is reduced by 20%, cost will reduce, albeit not by the same amount, so there would be no justification in a 60% increase.

The other weak point about the calculation is the implicit assumption that the feed-in power is replacing coal fired power - since power consumption in most places is setting records, this is a pretty weak assumption. The truth is probably that only part, perhaps a very small part of the feed-in power would be replacing existing coal fired generation, and most would be replacing additional capacity.

John

[PhilipA]

I just looked up the tariffs for green power and it is in NSW an additional 5.995c Kwh for 100% green and a flat $13 per quarter for 10% green.

I wonder how many people would be voluntarily paying an extra 50% at the moment ??? eg approx 6c on 12cents. I would bet that it is < 5% .I would be interested to know numbers but they do not appear readily available on the net.(surprise)

I seem to be the only one willing to research the numbers etc and I cannot be bothered any more.

However I just read some interesting stuff on a number of "green " sites which state that "dispersed" solar power is not the way to go, but Concentrated Solar Power(CSD) is what California is banking on. There is an Australian who has moved to California to implement it.

One site I looked at said the greatest gains in greenhouse will be from energy conservation. I wonder how that gells with the increasing demand in Oz from aircons.LOL
Regard sPhilip A

[JDNSW]

I just looked up the tariffs for green power and it is in NSW an additional 5.995c Kwh for 100% green and a flat $13 per quarter for 10% green.

I wonder how many people would be voluntarily paying an extra 50% at the moment ??? eg approx 6c on 12cents. I would bet that it is < 5% .I would be interested to know numbers but they do not appear readily available on the net.(surprise)

I seem to be the only one willing to research the numbers etc and I cannot be bothered any more.

However I just read some interesting stuff on a number of "green " sites which state that "dispersed" solar power is not the way to go, but Concentrated Solar Power(CSD) is what California is banking on. There is an Australian who has moved to California to implement it.

One site I looked at said the greatest gains in greenhouse will be from energy conservation. I wonder how that gells with the increasing demand in Oz from aircons.LOL
Regard sPhilip A

Interesting comments, particularly about the aircon, although in at least some cases the increases are at least partly balanced by reduced energy use in winter where reverse cycle systems have replaced resistive heating systems.

From a purely economic point of view, concentrated solar power is more attractive, and is also preferred by power companies and unions. But there are two advantages of the dispersed model. The first of these is that a significant proportion of the cost will be borne by committed conservationists rather than the power company, and the second is that it helps to make the system more robust and fault resistant, as well as deferring the need to improve the distribution network.

I agree that the major gains are to be made from energy conservation - but this is not going to happen unless the cost of power is substantially increased. There is plenty of room for it to happen, but almost everything you do to conserve energy costs money, and most people will not do it unless it saves significant amounts. Like driving - in almost all normal circumstances, the cost of fuel is way down on the list of costs (usually around 25%) for a vehicle, and for there to be an economic reason to conserve fuel, the price has to increase drastically.

John

[isuzurover]

I always seem to be the Cassandra but i was just thinking of theimplications of this subsidy to buy solar for reinjection to the grid in SA detailed by Spudboy.

Some BOE calculations.

Say Normal power costs the distributor 10C per Kwh.( probably very generous)
The subsidy for injecting solar is 44c Kwh. and it appears from the offer that the 1Kw setup is designed only to inject power back into the system. No batteries are mentioned.

If 20% of power were produced by solar, then coal/solar power prices would have to rise by 60% to 16.8c kwh to compensate.

So you buy the 1Kw set up plus solar HWS for $5490

If you can generate 3kwh per day average summer /winter /sunny /dull then you get $9 per week or $450 per year, so you get payback in 7-8 years.
BUT , seeing you are selling it all back into the grid, you still have to use all the energy you are using now.

Now the more people taking up the option the more expensive electricity will come, so that at the end of the day you will pay 60% more for your power!!!

So say you pay $1000 per year now you will pay $1600.

So you gain $450 and lose $600.

BUT you feel really good about yourself for being a committed conservationist and are happy in the knowledge that all those who did not put solar on are paying much more.

Regards Philip A

It isn't quite as simple as that.

Coal power costs about 4c/kWh to generate, and lets assume maybe 8c for the distributor.

AFAIK, if you install a grid interactive solar system, you don't get to sell ALL the power back to the grid, only your surplus.

However the companies are happy to pay you a premium, because:
(a) they can use/sell the carbon credits from the power you generate
(b) if it means they can delay the construction of new power stations, they are saving money overall.

[lil-landy]

5.5k!?!?!?!?!?!

Just paint some radiators black and bodge in a bit of piping if its just hot water you want.

[lyallthecrocodile]

some quick points, here in SA there are two companies now paying $0.66 per kwh generated from our solar systems. also as an electrician we generally tell people (though i haven't done the maths lately) that installing a solar hws will cut their power bill by roughly 30% (obviously depends on size of family and length spent in shower etc!). one other point is that depending on who you know, it can save a lot of money if you install the hws yourself and just have a plumber do the connections or check it and sign it off for you (the average installation cost is $700 for solar hws if you just get the company to do it for you). it is a bit of fun getting the tank on the roof though! :)

[Captain_Rightfoot]

I think Solar HW makes sense, but like Spudboy our conventional electric HW only uses around $50 a quarter. So, you just can't justify switching for switchings sake. I guess what I'm saying is I will consider it when we're at the point where I think the existing one is going to kark it.

Also, I'm believe that the new heat pump HW systems actually use similar amounts of power to solar by the time you take into account the electric backup and water pumps that some of them need.

Shortly, I'll have a good look into that. It may well be that the two systems use a similar amount of power, but one attracts a government subsidy. :)

[Blknight.aus]

ATM my solar gear is all my camping stuff and is 12v /small scale

but it works well enough to run indefindately (well in most of queensland and the summer at albury) out bush without needing to run the vehicle.

It also supplements the house in the event of a power outage.

I'm not keen on doing it for the house ATM no-one sells a to go kit for the handyman (accepting that Id have to hire a sparky to do the final hook up and a plumber to put the water side on) but I am strongly considering it.

[johnb44]

i am a plumber and carnt really comment on the heat pump hot water systems as i am yet to instal one but i will be putting one in in the next couple of weeks
but i have done several solar systems and am not really convinsed that there is alot of savings to be had sure you get a rebate but your purchase price is nearly triple of a normal size hot water service and the pannels can break as well and the tank probally wont last any longer than a normal one then you have a pump to circulate water to the pannels let alone the replacment costs of all the different valves that will last about 5 years maybe a bit longer
so whatever makes you feel good is the go
ill update after i have installed the $3000 odd heat pump hws in the near future

[JDNSW]

.........
but i have done several solar systems and am not really convinsed that there is alot of savings to be had sure you get a rebate but your purchase price is nearly triple of a normal size hot water service and the pannels can break as well and the tank probally wont last any longer than a normal one then you have a pump to circulate water to the pannels let alone the replacment costs of all the different valves that will last about 5 years maybe a bit longer
so whatever makes you feel good is the go
.............

Your figures are interesting - my solar hot water system is fourteen years old and has never needed any parts replaced (possibly helped by the fact that it runs rain water). It uses a gravity feed tank in the roof and a frost valve on the collector for frost protection. There is no pump to circulate the water as the collector is below the panel.

John

[johnb44]

Your figures are interesting - my solar hot water system is fourteen years old and has never needed any parts replaced (possibly helped by the fact that it runs rain water). It uses a gravity feed tank in the roof and a frost valve on the collector for frost protection. There is no pump to circulate the water as the collector is below the panel.

John

being a gravity feed tank you should get 30+ years from it :cool: unfortunatly mains pressure ones wont last as long ,there are alot of factors to it to like water quality etc so there is no hard and fast rule to it all but the last post has been my observations from being in the industry for 29 years ;) and there are always the ones that suprise you to :angel:

[rar110]

Sorry if the following is a bit long. Go the last two paragraphs for the 2 second summary.

We installed an Edwards gravity fed solar h/w system as the electric was about to die (confirmed when removed - badly rusted inside). We picked Edwards as had one before and has stainless tank. We were averaging about 5 to 9 kWh per day on the hot water. That is down to zero since August (electric boost not connected yet). The water is very very hot. The Fed Govt contribution was $1000. We paid $2800 after the rebate and RECS.

The Fed Govt contribution to PV panels is $8000 for a 1 kW system that generates 4 to 5 kWh/day, less power than our solar HW saves. IMHO the Govt should increase the incentive to go solar h/w or heat pump. However, the Fed Govt contribution might result in more R & D on PV resulting in tech advances.

We are installing a 2 kW system that should give us 8 to 10 kWh/day. We have a small well ventilated house that uses between 9 to 11 kWh/day. So a 2 kW system should cover all our energy needs. It will cost $14,000 after the Fed Govt rebate (before RECS).

Current retail cost of peak supply electricity in Qld is 14 or 15c / kWh, in Japan is 30c and UK 35c approx using currency conversion. So Qld power is very cheap. Wholesale electicity prices are predicted to double by 2015. The current feed in tarif is 44c /kWh.

I have estimated that a 2 kW system costs about the same over 25 years has buying electicity at current prices. It is a bit cheaper per year than buying Greenpower. The annual cost of PV was estimated by totalling the benefit (electicity savings + income from feedin tarif) minus costs (depeciation and loan repayment at 7%). PV comes out in front if electicity prices reach that of UK, but only by $100 to $200 per year.

Green power is an excellent option for those not wanting to spend a lump sum on a PV system. More demand for Greenpower will mean more Greenpower infrastructure investment. Solar turbine, windpower and geothermal are more economical than PV.

[Slunnie]

Im currently building and have just decided to not fit solar, but instead a heat pump tank. Admittedly I live in a cold climate so I probably would have gained limited amounts from a solar setup, but the complexity, risk of break down with the additional systems and cost of a better system has driven me back to a heat pump setup for something that is still cheaper to run, simple and reliable.

[rar110]

Im currently building and have just decided to not fit solar, but instead a heat pump tank. Admittedly I live in a cold climate so I probably would have gained limited amounts from a solar setup, but the complexity, risk of break down with the additional systems and cost of a better system has driven me back to a heat pump setup for something that is still cheaper to run, simple and reliable.

I fitted a solar HW to a house about 10 years ago that was in a frost area. The panels faced north so had full sun (no shade). We only needed to use the electric boost 3 or 4 days a year at most. The panels have become more efficient since then and more frost resistant. Solar HW with a gravity fed roof tank is pretty simple as has no electric motor. Heat pumps are a huge improvement over electric and probably $1000 less initial outlay than solar HW. However, you should consider maintenance and depreciation (expected life of system). Most units have sacrifical annodes that are recommended be replaced every 3 to 5 years or somethin (unless you get one that has a stainless tank).

[srowlandson]

in regards to Solar Power, a standard 1 - 2Kw system ($4-10K) I have often seen customers go from $200 a qtr bills to going in credit.

Getting solar is the first step, but learning to be wise with power can see you actually turn your bills into cheques.


A few things to consider.

you only sell the power you generate but don't use... if your house is pulling 3 kilowatts and your solar is generating 1, then you using it and buying 2 from the grid. So... you don't use power thirsty appliances when you generate.. i.e. during the daylight... you run things like washing machine, dryer, dishwasher etc at night.

if i owned a home, i would most definately get a solar power setup... if you use them wisely you can do well.. my numbers say payback on investment is about 4 years.. which is pretty damn good. And I work in the Electricity industry and see customers Solar bills daily.

Steve

[BigTim]

Okay - first up the disclaimer - I am a BCSE accredited grid connected photovoltaic designer / installer (solar electricity) in NSW so I am unashamedly in the FOR camp.

Now, onto the reasoning, realistically the most effective ways to reduce your home energy usage are, more or less in order of energy effectiveness:

1) Replace / reduce use of energy intensive appliances - e.g. low voltage halogen lights, unplug appliances when not in use etc. Believe it or not the average 1kW microwave oven will use more energy over a year in "standby" mode keeping the clock running than it will actually cooking meals......

2) Ceiling (and wall / underfloor) insulation. By reducing the amount of heat being lost through your ceiling/walls/floor you drastically reduce the amount of energy required for space heating.

3) Solar Hot Water system. If you have an electric storage hot water system, take a look at your power bill and notice the amount of energy being used on the "off-peak" tariff. That's all being used to heat the water in that tank overnight. Given the available rebates etc this is a worthwhile investment - while the current off peak pricing is low it may not seem worthwhile but electricity distributors in NSW have just had approved an approx 20% increase in pricing for network upgrades and I would be willing to bet that other states are not far behind. Add to that the roll out of Time Of Use metering (TOU) by all retailers which measure your power usage in 30 minute intervals and allows for multiple tariff rates. My suggestion is that you also research "evacuated tube hot water systems" as they more or less eliminate many of the problems of the flat plate systems (e.g. freezing overnight, breaking one or two tubes does not cause leakage or total system failure, no need for glycol mixtures etc) and can be combined with a remote mounted (i.e. ground level) tank if so desired.

4) Photovoltaic system. Yes - even though these are my particular niche they fall at the bottom of the list for energy effectiveness as they are relatively expensive compared to their overall energy output. Same comments as for 3) regarding increasing cost of electricity. Payback period depends on multiple variables - buyback rate from your electricity retailer, your energy usage pattern through the day, system output.

Notice - I say throughout this post energy usage rather than cost - this is because there is more to energy usage than the immediate dollar cost. Other things to consider are carbon dioxide and particulate emissions from coal-fired power stations and the mining / transportation process.

I have no affiliation with the company(s) listed in the earlier / original posts - however in my opinion the parts being specified for the photovoltaic component of the deal are of good quality and are some of the best recognised brands in the field (e.g. SMA inverters, BP / Sunpower / Suntech panels etc). My suggestion would be go for it - I doubt you'll regret it.

If anyone wants a second opinion about systems they've been quoted feel free to ask - I'll need a couple of details about your location and what parts you've been quoted so I can calculate PV system output etc. One important thing to bear in mind with ALL the PV suppliers out there right now is that system outputs are being quoted under "Standard Test Conditions" (STC) i.e. lab conditions, not realistic operating conditions. As a result panel heating, and various other factors come into play and reduce the actual output of your system, (e.g. the oft quoted 1kW domestic system frequently only puts out about 750 - 800 W of instantaneous power even under full sunlight).

IMPORTANT NOTE: The $8000-00 SHCP rebate ends June 30th 2009, if you want to get it you need to send in your pre-approval paperwork quickly - this is a pre-approval only, you are not committed to going ahead with the installation unless there are sneaky terms and conditions by whichever installer you get to provide the system details. Once your application is in however there is around 9 months to actually get the system installed while you can still claim your rebate.

[p38arover]

I'm considering solar power, maybe a 2-3kw unit in order to offset the cost of power for my ducted aircon which consumes 5.7kw at max load.

Unless I am misreading the solar guff, it seems that, in NSW, I would be eligible for the gross feed-in tariff of 60 c/kwh whilst consuming power off the grid at 16c/kwh.

Solar Bonus Scheme for NSW | Industry & Investment NSW (http://www.industry.nsw.gov.au/energy/sustainable/renewable/solar/solar-scheme)

This looks a better deal than using my own solar power to supply part of my electrical load (net feed-in).

NSW Solar Bonus Scheme - frequently asked questions | Industry & Investment NSW (http://www.industry.nsw.gov.au/energy/sustainable/renewable/solar/solar-scheme/faq#What-is-the-difference-between-a-'net'-and-a-'gross'-feed-in-tariff)?

This way, the payback period would appear to be fairly short.

Or am I confused?

[Captain_Rightfoot]

Ron, I'm pretty sure you only get paid for your net output. Ie.. if you generate 7kw in a day and use 5kw you get paid the "special" rate on just the 2kw difference. This is how it is in qld, anyway.

[p38arover]

The new NSW scheme appears different to the Qld scheme.

[bee utey]

I'm considering solar power, maybe a 2-3kw unit in order to offset the cost of power for my ducted aircon which consumes 5.7kw at max load.

Unless I am misreading the solar guff, it seems that, in NSW, I would be eligible for the gross feed-in tariff of 60 c/kwh whilst consuming power off the grid at 16c/kwh.

Solar Bonus Scheme for NSW | Industry & Investment NSW (http://www.industry.nsw.gov.au/energy/sustainable/renewable/solar/solar-scheme)

This looks a better deal than using my own solar power to supply part of my electrical load (net feed-in).

NSW Solar Bonus Scheme - frequently asked questions | Industry & Investment NSW (http://www.industry.nsw.gov.au/energy/sustainable/renewable/solar/solar-scheme/faq#What-is-the-difference-between-a-%27net%27-and-a-%27gross%27-feed-in-tariff)?

This way, the payback period would appear to be fairly short.

Or am I confused?
You lucky man, having a gross feed-in tarriff (I read the link). This means you will be paid the full amount for every kWH your panels produce, something like $1000 p.a. from a 2kW system. Here in SA we still have a net metering tarriff of around 50c per kWH, this is paid for the power your house is returning to the grid, while you are not using it. I think they did that to encourage consumers to run their houses at the lowest consumption possible during the day, otherwise you lose the high feed-in rate.
In either case you have to have an electronic mains meter that can measure which way the juice is flowing.

[hoadie72]

I'm considering solar power, maybe a 2-3kw unit in order to offset the cost of power for my ducted aircon which consumes 5.7kw at max load.

Unless I am misreading the solar guff, it seems that, in NSW, I would be eligible for the gross feed-in tariff of 60 c/kwh whilst consuming power off the grid at 16c/kwh.

Solar Bonus Scheme for NSW | Industry & Investment NSW (http://www.industry.nsw.gov.au/energy/sustainable/renewable/solar/solar-scheme)

This looks a better deal than using my own solar power to supply part of my electrical load (net feed-in).

NSW Solar Bonus Scheme - frequently asked questions | Industry & Investment NSW (http://www.industry.nsw.gov.au/energy/sustainable/renewable/solar/solar-scheme/faq#What-is-the-difference-between-a-'net'-and-a-'gross'-feed-in-tariff)?

This way, the payback period would appear to be fairly short.

Or am I confused?

Your reading of this is in line with what a guy at work told me. He's funding his through a Green Loan , while not free, does spread the costs out over a number of years. I believe he's installing a 1.5kW system.

http://www.environment.gov.au/greenloans/guidelines/index.html

[Banjo_pluker]

The NSW way is you do get payed the full 60c per Kw produced for the 7 years. This means you will get a power bill for the full power you produce. Country Enegy will give you a credit for this amount on your bill every quarter above the amount you have used.

At the anniversary date you can request a payment for your credit.

In regard to the amount that they pay you, the rate is fixed for 7 years but the rate that they sell power to you is not and this price may and has been rumored it will rise.

In saying all this we are probably about to purchase a 1.5kw system