Future Proofing Solar Installation

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eonsim

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#2891645 24-Mar-2022 19:58

insane:

Interesting, that's a great comparison! My daily average over the year is also around 20kw+, and I'm the same with gas hot water, gas heater (not used) and 6 heatpumps (seldom all used at once).

I created a big spreadsheet and found payback period was longer than I'd want to stay in the house. Add batteries and it got worse as my nighttime usage is rather minimal.

Was your viability done on the basis of a low user daily power charge or a higher / standard $2+ per day daily rate? I heard that the low user plans will be grandfathered soon due to new legislation? That alone would make a $50 or so per month difference.

We have a 5.1kw system on a Fronius inverter and REC Alpha panels on a NNE facing and some tigo optimisers, as we have a bit of shade in the afternoon/evening. I would have liked more panels, but the roof size and shape didn't really allow it.

We typically use 28-34kwh a day, since we've had the panels installed they cover ~45% of our usage (on average across the year), we use about 75% of the power we generate, export 25%. We also used the Westpac interest free solar loan which covered ~65% of the cost of the system. Based on generation for the last 9 months it'll probably be a payback time of around 10-11 years, assuming power prices don't increase in that time.

You can see the system generation here: https://pvoutput.org/list.jsp?userid=96957

Quinny

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#2892010 25-Mar-2022 11:47

insane:

Interesting, that's a great comparison! My daily average over the year is also around 20kw+, and I'm the same with gas hot water, gas heater (not used) and 6 heatpumps (seldom all used at once).

I created a big spreadsheet and found payback period was longer than I'd want to stay in the house. Add batteries and it got worse as my nighttime usage is rather minimal.

Was your viability done on the basis of a low user daily power charge or a higher / standard $2+ per day daily rate? I heard that the low user plans will be grandfathered soon due to new legislation? That alone would make a $50 or so per month difference.

Yes low user plans are going. At the moment Genesis who I am with have not advised any changes. I am 30c a day, 30c usage and 12c back.

Viability was on basis of "I want to do this". For me the fun of having the system, feeling intendent from the grid for most of the year and being green was a big factor. Second was if I sold the property the system was seen as having value equal to or more than what it cost as I had the Powerwall as well. I really do feel that payback on panels is superb, Powerwall much less so if just looking at "how much do I save a week" but this was not my main diver for going ahead. The Powerwall means I have full house backup capable of running the whole house. I can then turn off what want to use only a little if needed if the day was crappy or power is down. But power cuts are random the major use is to provide low cost power for what you cannot time shift (eg use during they day such as dryer, washing machine, dishwasher). Here its fantastic and I wish I had 2.

insane

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#2892104 25-Mar-2022 13:36

Wow that's for that guys, that's super useful! Sounds like I should try upsize the system a little to make it more worthwhile.

insane

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#2895550 1-Apr-2022 23:41

Mercy Energy - Electricity Price Review PG5

Toward better network solutions
Mercury agrees with the assessment in the EPR First Report that driving greater efficiency in our distribution and
transmission networks will be essential to ensure costs for consumers are kept as low as possible in the future.

There is considerable industry consensus that the Low Fixed Charge Tariff (LFCT) regulations should be
removed. Mercury supports a phased transition over a five-year period to ensure this is manageable for consumers. The LFCT does not need replacing so long as distribution pricing reform is progressed and there is better
targeting of the Winter Energy Payment to ensure vulnerable consumers are protected.

The excessive variabilisation of lines charges needs to be addressed to deal with higher bills in winter.
Consumers favour simplicity over complexity and the evidence suggests a significant proportion of the benefits
from cost-reflective pricing come from simple pricing structures. We support progressively increasing fixed
distribution charges (in line with LFCT phase out) and introducing limited and most likely static peak signalling
to encourage efficient consumer behaviour.

A default cost-reflective structure should be introduced. This will deal with the regressive issue of current
network charges and send efficient signals for solar investment and electric vehicle charging which will also avoid
the need for unnecessary and damaging network control of such technologies.

I'm trying to unpick this section of the report, on the one hand it's saying that the industry (obviously self-serving) supports scrapping LFTC, but then suggests it's not actually necessary as long as the WEP payments go to those in genuine need.

Is it then also suggesting a cost model be introduced which better covers the true cost of energy transport?

And finally suggesting that pricing should be related to the peak KW drawn to allow those who do make an investment in solar to receive some benefit assuming their setup is able to limit peak usage.

Have I understood this all correctly?

Source: https://issuu.com/mercurynz/docs/mercury_electricity_price_review_fi?e=25554184/65480681

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