What price does PV solar have to be to make sense?

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Stan

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#174992 12-Jun-2015 22:05

Full disclosure not looking to advertise but I work for a retailer that is looking at getting into PV solar...

What would make you purchase a system is it payback time, yield or geeky interest?

NZ has relatively low market penetration why do you think this is?

Our entry level system would be using canadian solar polycrystalline panels and Enphase micro inverters fully installed system would cost $5999.

Really interested in general feedback...

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#1323732 12-Jun-2015 22:17

My own Wishlist

Payback time should be 5 years or less, with some sort of guaranteed support and panel output ratio.
Install should be available countrywide (within reason) and
should include/enable a future proofing 'upgrade path' (ie mountings that are likely to be standard for fitting future higher-output/lower-loss panels)

Major cities should have 'display show-home' style working models so customers can see and know how the install will/should look and work for their own home too

Geek-speak is great for us geekzoners (we LIKE knowing how things work) and should be available through support lines like email....

And so the list goes on... ;)

Stan

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#1323738 12-Jun-2015 22:32

PhantomNVD: My own Wishlist

Payback time should be 5 years or less, with some sort of guaranteed support and panel output ratio.
Install should be available countrywide (within reason) and
should include/enable a future proofing 'upgrade path' (ie mountings that are likely to be standard for fitting future higher-output/lower-loss panels)

Major cities should have 'display show-home' style working models so customers can see and know how the install will/should look and work for their own home too

Geek-speak is great for us geekzoners (we LIKE knowing how things work) and should be available through support lines like email....

And so the list goes on... ;)

Everything except the 5 year payback is what this system will offer and that's partly due to low feed in tariffs. You might be able to get closer with a super cheap imported system from china but don't expect it to last :P

Upgrade is relatively easy with micro inverters as opposed to DC because you don't have one single inverter so when evening/morning load batteries become more cost effective it would be cheapish to upgrade to more panels/ add a battery.

Thanks for the feedback :)

Aredwood

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#1323750 12-Jun-2015 23:20

PV solar will never really be suited to NZ due to alot of power already being generated from renewable sources. And Peak demand being in mornings and evenings. This means almost no environmental benefit of grid connect solar. (solar peak production in when there is alot of renewable power available).

So the benefit has to be financial. But payback periods are based on projections of future power price rises and tariff structures. And your usage patterns make a very big difference to payback periods as well. So this means some people will do very well with PV solar, Some it will help a little bit, And some will never recoup their install costs. So you need to consider how to either make sure you don't install systems for people who won't recoup. Or how to handle the claims of: Your system doesn't work as claimed / doesn't save me any money / A tariff structure change means I no longer save any money, ect.

Your system will need to offer diversion to a hot water cylinder as standard. And since you will be making the system from scratch - Make the diversion system modulating. The only off the shelf dirversion systems I know of are either full on or full off.

And I don't see how a future battery storage system could ever be efficient when combined with a micro inverter system. As you will be going from: Panels > micro inverter losses > battery charger losses > battery storage losses > Battery to mains inverter losses. So battery systems only make sense for off grid. Or maybe if everyone gets forced onto peak / offpeak tariffs. But if this happens then it would make feed in tariffs even lower.

Geektastic

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#1323752 12-Jun-2015 23:24

Stan: Full disclosure not looking to advertise but I work for a retailer that is looking at getting into PV solar...

What would make you purchase a system is it payback time, yield or geeky interest?

NZ has relatively low market penetration why do you think this is?

Our entry level system would be using canadian solar polycrystalline panels and Enphase micro inverters fully installed system would cost $5999.

Really interested in general feedback...

Low penetration because, unlike quite a number of countries, no government subsidy appears to be available to cover some of the cost involved.

It's hard to assess at what point I would get involved without knowing how much of our power would be produced.

For example, if it was 100% at $6000 I would write you a cheque tomorrow. If it was 10% I wouldn't waste the ink.

k1wi

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#1323777 13-Jun-2015 03:19

As with Geektastic, the answer depends on the question you're asking. Is it 'what price will enable you to enter the market', or is it 'what price would you be prepared to pay for an (unknown) capacity.

Personally, given the difficulty in forecasting future power prices out over the life of the panels and the upfront costs, I price a substantial premium for uncertainty. If I was marketed it on economic returns, over say the environmental benefits, I expect to see rigorous analysis to back up any payback periods. Too much that I have seen is overly simplistic or over-optimistic. Even just taking into account the falling cost of panels is often overlooked in any analysis.

k14

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#1323778 13-Jun-2015 06:24

k1wi: Personally, given the difficulty in forecasting future power prices out over the life of the panels and the upfront costs, I price a substantial premium for uncertainty. If I was marketed it on economic returns, over say the environmental benefits, I expect to see rigorous analysis to back up any payback periods. Too much that I have seen is overly simplistic or over-optimistic. Even just taking into account the falling cost of panels is often overlooked in any analysis.

This is the biggest one, given the uncertainty surrounding future power price increases I would want a 5 year pay back. The biggest problem is that the power companies are able to dictate prices and if they perceive a threat could change things in one fowl swoop to ensure they keep the ascendancy. Add to that the fact that the lines companies which are a monopoly can change their pricing regime any time they want and more heavily weight the line charges towards peak demand and that could negate any gains made by you installing the solar. The only way to get around this is to have your own storage to ensure both your net demand and peak demand is reduced. The only way to do this is via battery storage. The day is certainly coming (probably in the next 5-10 years) but as of yet it is not here.

I believe the race of distributed vs centralised generation in NZ comes down to electric cars vs batteries. If the battery storage matures before EV's become widespread in NZ then the power companies, transmission and distribution infrastructure will enter a death spiral that may not be able to be reversed (without government intervention). If the power companies wake up and get the penetration of EV's more mainstream then that will ensure they continue to have the ascendancy and the current situation of 10+ year pay backs will continue to be the norm. Although this doesn't take into account of a step change in either EV or PV/battery technology. If that happens then all bets are off.

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timmmay

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#1323816 13-Jun-2015 08:52

Storage is really necessary in NZ to shift the production to the time the power is needed. When I can get a system for $10K (or maybe $20K, but probably $10K) that will absorb enough power during the average day to power my home on an average day, that's when I'd be in.

Geektastic

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#1323824 13-Jun-2015 09:02

timmmay: Storage is really necessary in NZ to shift the production to the time the power is needed. When I can get a system for $10K (or maybe $20K, but probably $10K) that will absorb enough power during the average day to power my home on an average day, that's when I'd be in.

Can we use those flashy batteries that Elon Musk is selling?

k14

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#1323842 13-Jun-2015 09:42

Geektastic:
timmmay: Storage is really necessary in NZ to shift the production to the time the power is needed. When I can get a system for $10K (or maybe $20K, but probably $10K) that will absorb enough power during the average day to power my home on an average day, that's when I'd be in.

Can we use those flashy batteries that Elon Musk is selling?

No reason why not, I think Vector has struck a deal with them. But, 10kWhr storage for $3500USD is still a while away from being usable for 99% of the population. However, it isn't far away. All we need is a few interations of the technology (probably 50kWhr for $2-3k) and it will start to be come mainstream.

I had a smart meter installed 3 weeks ago and am using between 35-45kWhr per day. I live in Central Otago and use fire for most of my heating so in summer I could probably get by with a 50kWhr battery pack and a 10kW solar array quite easily. Winter is a different story though. I'd have to look at hot water heating and various other energy saving aspects if I was wanting to go off grid.

timmmay

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#1323850 13-Jun-2015 10:01

Geektastic:
timmmay: Storage is really necessary in NZ to shift the production to the time the power is needed. When I can get a system for $10K (or maybe $20K, but probably $10K) that will absorb enough power during the average day to power my home on an average day, that's when I'd be in.

Can we use those flashy batteries that Elon Musk is selling?

Yes and no. Yes they'd work, but no they're not suitable. Each has a 2kw output, so if you want to run your oven, hob, and a heat pump at the same time you'd need maybe six of them. Providing for peak load may be unrealistic though.

k14

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#1323851 13-Jun-2015 10:06

timmmay:
Geektastic:
timmmay: Storage is really necessary in NZ to shift the production to the time the power is needed. When I can get a system for $10K (or maybe $20K, but probably $10K) that will absorb enough power during the average day to power my home on an average day, that's when I'd be in.

Can we use those flashy batteries that Elon Musk is selling?

Yes and no. Yes they'd work, but no they're not suitable. Each has a 2kw output, so if you want to run your oven, hob, and a heat pump at the same time you'd need maybe six of them. Providing for peak load may be unrealistic though.

I believe you can daisy chain 10 of them so for $35k USD you'd be good to go :) Plus probably another $30k for solar to charge them.

In all seriousness though, that is pretty cool that for around $100k you could be totally off grid and retain a modern lifestyle. We just need the cost to come down by 90% and I'll be in.

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k1w1k1d

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#1323892 13-Jun-2015 10:52

Our electricity totals for last 12 months;
3,416 night units @ 11.59c/unit = $395.91 +GST -10% discount = $409.77
3,252 day units @ 29.23c/unit = $950.56 +GST -10% discount = $983.83
Genesis Pricepark Classic day/night.

Night usage includes water heating, dish washer, and first washing machine cycle each morning.

You would have to prove to me how by installing your system, paying interest on loan, and us changing the timing of above, that we can pay off the system in 5 years.
I would want costings done on current power prices. Can't predict future prices, and what will happen if Comalco pulls out. Meridian may drop prices because they have an over supply of cheap hydro power?
Would also want to know how many years the system will operate so that I can actually make a profit, not just recover costs.

I think that you would have a hard sell to convince me.

sbiddle

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#1323898 13-Jun-2015 11:13

The very real (but harsh) reality of solar right now is that there is no ROI that really makes financial sense.

Yes people selling solar can quote all sort of figures to show that there is, but much of that is based on very optimistic pricing, and selling power back into the grid, something that is fraught with issues in itself. The electricity grid was never designed to have generation capacity fed locally into it, and moving to a future model where that can be accommodated (which is a cool concept in itself) would require some significant redesign of the electricity grid. All of that poses the question - who should pay for that? The householder who doesn't care about solar, or the people with solar who want to be an electricity generator?

Until off grid batteries are affordable there will already be big questions about ROI. We're on the verge now of significant battery technology redesigns that could make this reality in the next 10 - 20 years, but there is there is one thing that is certain, it's the fact we can't be certain about that!

richms

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#1324051 13-Jun-2015 14:14

The install cost needs to get under control.

Typical problem of high NZ labour costs and really expensive mounting systems dwarf the costs of the panels. Hell, the panels could be free and it would still cost too much to install in NZ.

Richard rich.ms

raytaylor

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#1324346 14-Jun-2015 09:28

It requires a lifestyle change.
In australia and various other countries, power companies are opting not to buy back power any more since they are not required to.

So net metering might not be around for much longer, increasing the payback time.

Personally right now i wouldnt look at anything less than a 8kw system if i was net metering since the panels are so cheap now, and the inverter / grid tie is pretty much the same cost no matter what size you go for. You might as well make back what you can while net metering is still around.

The solar industry needs to be pushing for some drastic law changes
- Mandated net metering option by all power companies
- All new houses of at least 5 bedrooms or more need a solar installation before occupied.
- All new houses need a north facing roof if the pitch is more than 25 degrees so a future home owner can opt for solar if they want to install a system in the future.

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