It’s always best to maximise your self consumption when the FiT is less than the cost per kWh.
3 Likes
It’s hard to make solar work where we live, trees, roof facing the wrong direction, low feed-in and we’re usually at work when the sun is highest. Instead we got a high quality heat-pump water heater. Saves us a lot and I reckon a payback time of 3-4 years. Stainless steel construction so it should last at least 20 years.
1 Like
Well done.
We did that at our previous residence and dramatically slashed our electricity usage and costs for hot water.
Hi @Matmatmat, welcome to the community.
High feed-in tariffs is about making money from solar electricity exported to the grid (there are arguments that this causes increased electricity costs across the board as someone has to pay for the generous feed-in tariffs).
Low feed-in tariffs is about saving money by not having to import/use more expensive electricity from the grid.
In relation to your comment you are at work when the sun is at its highest, this usually means that north facing panels with a low feed in tarrif doesn’t make sense for you. If you consume more energy in the late afternoon when sun is still shining (e.g. set aircon for starting before you arrive home, cooking food, pool pumps etc), then west or north-west facing panels make sense and would assist in saving money from electricity otherwise imported/used from the grid. Likewise if you are a heavy morning user, east or north east facing panels would make sense. If you are both, then different strings of panels facing both easterly and westerly could make sense.
A good solar system designer would be able to assess your power usage, when itnis used and if alternative facing panels provide any long term financial benefit.
If you have trees all around the house shading it for most/all of the day, then solar possibly won’t be a financial option unless you have another place on your property to set up a system (shed in the sun, cleared area for ground mounted system etc).
3 Likes
While I’m sure Plendo is correct, I’m just simply comparing bills from previous years, with bills since solar.
Mainly because when we installed solar, we took the opportunity to get rid of all gas heating. So there’s no way to make a “correct” comparison, apart from comparing bills.
And yes, we’re on track to get “pay-back” in about 4 years, after also taking into account the reduction in the gas bill.
But coming up in a couple of years is the “big one”. We intend buying an EV, one that is designed purposively to be used as a “house battery” as well. After that our savings will be 2/3rds of the cost of the solar installation.
Tell me one other foolproof way to invest your money for a net after tax return of 66% !!!
Wait - there’s more! We never “spent” money installing solar. We simply exchanged X dollars from “cash at bank” and converted it to X dollars - “home improvements”. And because the panels were subsidised, the value of the increase in home improvements is a lot more than the dollars we took out of the bank, to do it.
And I don’t have to snivel about lumps of coal to justify my existence. We are proudly contributing to the reduction of carbon emissions. Even though we’re elderly and have no children, we CARE.
We care about the environment. We care about the global climate crisis. We care about the animals, birds, insects, reptiles and marine creatures. We care about the Great Barrier Reef. We care about the quality of the air everyone breathes. We care enough about the world that we will be leaving behind, to do whatever we can to leave it in the best possible condition.
2 Likes
ccmpl, I commend you on your attitude, I find it refreshing to have someone express basically what we all know to be right.
A year ago, we were living in a small rented townhouse with minimal if any insulation, gas heating, cooking, and hot water, our Winter energy bills averages $17.92 a day. We now live in a house we built (yes we did everything that did not require a licence), it is well insulated, all electric, with the most efficient devices we could find (heat pump water heater, heat pump clothes dryer, reverse cycle aircon, etc.) we are also 583 meters higher. Our power bill averages $6.46 last winter. Yes comparing the total cost makes perfect sense, but in our situation it does not tell us how much financial benefit we get from the solar.
Interesting to do the sums on a battery, I don’t think it makes sense yet, but they are not far away.
2 Likes
They might be further away financially than what battery manufacturers/suppliers/installers indicate. Battery prices haven’t decreased as forecast and they are likely to only become financially viable if grid electricity costs increase substantially. Currently they are only have a financial benefit if one is off grid and is looking to connect to the grid. The costs to connect to the grid, especially for non-urban residences, can be similar to or more than an off grid PV battery system. This is currently where home battery systems make sense.
Looking at new technologies like lithium ion, flow batteries etc, the other issue is reliability. Current testing indicates that there is some work to improve their reliability.
More about home battery systems, including reliability information, are discussed in this thread…
There is also thought that potentially massive grid based storage systems (battery farms, pumped and traditional hydro etc) make more sense financially for the community as a whole than individuals installing their own home batteries. This is due to economies of scale and that it is cheaper per unit of energy installed. These storages are also actively managed rather than set and forget like home battery systems.
1 Like
Assume by ‘makes sense’ deliver cheaper household electricity than buying coal and gas generated electricity?
As @phb suggested there are benefits to the grid when battery systems etc are distributed in larger installations. The costs at scale are also less than a home installation.
The battery reliability trials which are in place are useful, and designed to stress test each sample. It would also be useful to have some alternate performance and reliability data from those units that have been sold to Aussie consumers. More than 20,000 small scale systems have been installed with residential users each year.
That’s enough volume to have some confidence that most users have had successful outcomes, and the systems are not inherently unreliable in everyday use.
From a purely economic view point there are many things we do everyday that do not have a financial return, that cost us money. Some of us have our treasured pets, more than one. Many of us think nothing of the expense of feeding, grooming, vet services, toys and time in exchange for feeling good because we get that unconditional love and respect in return. I gather there are also those in the community who get the same feeling from a big fat battery and inverter connected to their solar PV while feeding excess to the grid. It does not always need to pay a cash return to make you feel good. I stroke our PV inverter daily. 
the OSD controls are touch and contact time sensitive. One way to check the system performance as I walk passed it near the front door.
A well sorted home battery reduces PV feedin during the day and reduces the evening peak demand. Both of these outcomes help the NEG run more efficiently, reducing CO2. Importantly the reduction of peak evening demand flattens the duckbill. A further outcome is less peak demand reduces the premium generators receive to service peak loads. It’s the greater earnings from meeting these peaks that is driving investment in large scale battery farms. Most home battery owners get no financial return for doing so, despite the reality they are helping to push down the wholesale cost of power. Hopefully we all benefit at the retail end.
2 Likes
