2017: Suppliers Strike Back

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2021 – Hot Water to Gas >>>


Grid usage down – Grid prices up

Electricity dollarsElectricity and gas suppliers have recently announced massive increases in the cost of their energy supply. Around 19% in one hit – taking effect from 1st July 2017.  (Read more about this at the SMH

Is anyone surprised?

Our anti-renewable fossil politicians claim that this increase is due to the impact of ‘renewable energy’ – not quite true of course, as outlined by Peter Martin.

As detailed in earlier posts on this site, our household has made great efforts to reduce electricity consumption, and endeavoured to use our own solar-generated electricity to meet our remaining daily needs. (We live in Kiama on the south-east coast of Australia.)

It is this reduced consumption from the grid that is, in part, driving the increased per-unit costs being imposed by the providers – they will insist on maintaining (or increasing) their profits despite decreasing need for their product. So in that context, the move by consumers to renewable energy is increasing the cost of grid-supplied energy.

Previously it has been argued that the cost of a solar installation is not worth the savings that are generated through lower electricity usage from the grid. I beg to differ, especially now as grid providers continue to increase their cost of supply. Every unit cost increase by grid providers is another saving for those who have opted for the solar alternative.


Has solar made a difference?

Lets look at a comparison of pre- to post-solar costs in our household – with a consideration of what our electricity would be costing us had we not installed solar panels, by applying current grid rates to our pre-solar grid consumption …

Costs chart - before and after solar

Based on the new rates (July 2017), had we not reduced our electricity consumption we would be paying $1,783 for our electricity for the Sept/Oct/Nov billing cycle. Or approximately $7,100 pa. (And this doesn’t include what our provider now refers to as ‘supply cost’ of around $1 per day, regardless of how much energy is used.)

Instead, through a combination of self-generated solar supply and careful use of energy, our projected cost of grid-supplied electricity for the same period in 2017 (with the new rates) will be $536, or $2144 pa.

That is a saving of nearly $5000 pa.

Which makes the original $6000 cost for our solar infrastructure (in 2015) not such a bad investment which, based on current energy costs, paid for itself in savings in around 14 months.

We still don’t produce enough solar-generated electricity to be completely off the grid. Unfortunately our swimming pool pumps are a big  user of our solar electricity.

Our next step is to increase our solar-generated electricity excess and harvest this excess to a battery for use at night, for even less reliance on the grid providers. However, given current battery capacities, we would need two batteries, and they cost around $8000 each – which is not likely to be recouped as quickly as was our investment in solar panels.

We need battery costs to decrease and capacities to increase before they become a viable proposition for us.


Some comparison graphs – usage and costs

Graph - costs vs usage

Graph - costs pre and post solar


See also: SMH – reducing energy costs >>>


<<< 2015 – Going Solar

2021 – Hot Water to Gas >>>