Thread: Just getting started on Solar HWS/Power investigations

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

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

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

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.

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

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.

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

Originally Posted by 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

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