Solar start looking attractive to consumers when it is lower cost than retail.
That's been the case in Australia for many years now. If you have a suitable roof, it's a no brainer to put up a grid tied system here.
With net metering, that is on an amortized cost of watts over some years, or system life, or including time value of money when rates are higher.
Without net metering it only applies to the watts you're able to use immediately.
We have net metering here but excess production exported is credited at a fraction of the cost to buy from the gird. Exported energy roughly valued at the wholesale generation cost as the network/transmission charges are only added to energy purchased from the grid, not on energy supplied to the grid.
As a result, moving discretionary loads to daytime to increase direct self consumption of solar PV its still the most valuable use of the resource.
Rooftop solar costs 3x what utility scale costs, so if the goal is reducing fossil fuel consumption by installing PV, we would get 3x the benefit with utility scale PV plants.
That's true however it is very difficult for an individual to invest in and received immediate direct benefit from a solar farm. It's akin to buying shares in a bus transport service company. The cost per passenger mile is much lower than for your personal car but you don't personally get much use from the bus company services. Eventually you hope to receive some financial benefit by way of dividends or share value growth but you are at the mercy of the company's management.
I think PV backfed to the grid provides some benefits to the system. It is power available for users which would otherwise have required utility power plants (that have not been built.) If rooftop solar users all shut off their systems on a high-demand day, I think the grid would collapse.
Here rooftop solar PV supplied more energy to the nation over the past 12 months than did hydro power or gas fired power stations.
So poor people are benefitting from it.
It's swings and roundabouts here.
Rooftop solar PV has helped drive down daytime wholesale energy prices and is a sizeable source of supply for the grid (displacing daytime coal power mostly, which would have readily been able to provide that energy if needed), however it has come at the cost of increasing daily network service charges as the transmission network loses per kWh income on all the energy they are no longer supplying during the day.
So the network/transmission companies have had little choice but to recover those costs in other ways (it is highly regulated fortunately but those charges have been increasing as a result). And peak period energy pricing in the early morning and especially in the evening have been getting much higher as well.
This has disproportionately negatively affected the poor far more than the well off. It's why organisations here such as the St Vincent de Paul Society here have long lobbied for a better way to address cost of living imbalances the rapid uptake of rooftop solar PV has contributed to. They have a fair point. It's not the fault of the 25% of households who have installed rooftop solar, but rather of the current energy market design.
Rooftop solar PV here is not the most financially efficient way to generate energy, however it's more financially efficient for millions of homes because of the way the system works. It makes a sizeable contribution to servicing grid demand and has enabled more renewable generation into the system than might otherwise have been possible.
But we (Australia) needs continued massive investments in grid scale renewable energy generation, infrastructure and transmission if we are to navigate our way through this.
The flip side is getting back to the theme of the thread - energy conservation.
We are a bit overly focussed at times on the supply side. We also need to work on improving the demand side. Our atrocious house building standards when it comes the energy efficiency is a stand out example. Lack of draft proofing, lousy insulation etc.
The use of ever larger vehicles is another, which have completely eroded any fuel efficiency gains made with better engine design. The lack of investment in public and active transport options and a general anti-cycling/walking sentiment in anglophone countries. Just some examples of why we will struggle to turn this rather large boat around.
