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#2014249 11-May-2018 18:34

Jase2985:

sounds like you are already sold on it.

I think so.

My issue is paying this money and not owning it. There is a ticket clipping going on. A margin is being taken.

If solar PV is worthwhile, its much more worthwhile to add it to a mortgage (low interest) and reap the savings. Clip your own ticket so to speak.

Krullos

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#2015023 13-May-2018 09:55

Jase2985:

sounds like you are already sold on it.

I was sold on it.. have now had my mind changed.

I had a copy of their Agreement so was able to answer Aredwood's questions.

I thought it would be useful to add a summary of SolarCity's current offerings to this thread for anyone researching them.

I'm now considering buying a system outright and adding it to the mortgage which seems to be the wiser option of the two, provided you have the equity available in your property.

Thanks everyone for the thoughts and feedback.

MikeAqua

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#2016206 15-May-2018 11:28

We used a council scheme to put solar hot water on our previous house. One of the ones where you pay it back via an additional rate. The increase in rates was less than the decrease in power spend so for us it was worth it.

We sold before it was fully paid off. The people who bought the house saw it as a bit of millstone: Why should they pick up the debt etc. They may have felt they were paying for the solar system twice.

Based on that experience I can only imagine how a buyer would react to a house that came with the remainder of a 20 year contract. I wouldn't touch it.

My father is talking about getting solar at their place in Kerikeri. I'm trying to persuade him to just pay to have a quality system installed, rather than be beholden to some company. It's not necessarily the company you have to worry about. It's whoever ends up in charge if they go bust.

Mike

gchiu

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#2016227 15-May-2018 11:46

I was under the impression it was now cheaper to have PV panels installed to heat your water rather than putting solar hot water on the roof.

Once the water is hot enough, any further sun is not being utilized. Whereas with PV you still can use the power.

tdgeek

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#2016595 16-May-2018 06:33

gchiu:

I was under the impression it was now cheaper to have PV panels installed to heat your water rather than putting solar hot water on the roof.

Once the water is hot enough, any further sun is not being utilized. Whereas with PV you still can use the power.

Fair point. We have solar HW, love it. The other way to look at it is if you have solar HW and PV, the PV can be devoted to the house, and top up HW if needed. Our solar HW was $8000 in 2011, incl 300L two element cylinder and the tube array was the middle one to suit a 5 BR house. Payback wise, my HW is off the grid for 5 months a year, plus the rest of time it is a solar solution with grid boost, so the payback should be pretty good.

If you bought a PV solution, you can only generate a few hours a day, more in summer, and less on non sunny days, so the ability to cover HW and house using PV is variable. So is solar HW, but it is dedicated.

richms

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#2016596 16-May-2018 06:42

You are also limited in the amount of grid tied solar you can install, no such limit with thermal collection, so if your maxed out on what vector will let you get and use a lot of hot water it would still make sense to put it in.

Richard rich.ms

MikeAqua

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#2016628 16-May-2018 08:26

The other issue with SHW is wind. Performance drops dramatically when the wind is blowing. Even those light Southerlies in winter have a noticeable impact on heating.

Mike

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tdgeek

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#2016631 16-May-2018 08:30

MikeAqua:

The other issue with SHW is wind. Performance drops dramatically when the wind is blowing. Even those light Southerlies in winter have a noticeable impact on heating.

Due to cooling of the tubes? Never thought of that. I believe the tubes are encased in a Glycol type of liquid that stops freezing, they also seem to insulate a bit too, annecdotally. I might test the wind effect, although that will be quite unscientific.

Oblivian

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#2016636 16-May-2018 08:39

It'd be good to get some real system stats to see what the production cost v spot pricing is.

Unless I'm mistaken and the battery can take care of overnight hot water topup, power is nearly 4x on spot at morning shower time, right when PV production is low. Same with tea time. That's 20 pricey winters to offset with summers

tdgeek

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#2016638 16-May-2018 08:45

Oblivian: It'd be good to get some real system stats to see what the production cost v spot pricing is.

Unless I'm mistaken and the battery can take care of overnight hot water topup, power is nearly 4x on spot at morning shower time, right when PV production is low. Same with tea time. That's 20 pricey winters to offset with summers

If I had that setup, I'd be adding a timer to stop grid heating at peak spot prices. You could top up in the lower cost wee hours, and same in the daytime PV generating periods to cover evening showers

The more timeshifting that can be done, the better for solar PV, and also for solar HW

Oblivian

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#2016648 16-May-2018 09:11

tdgeek:
If I had that setup, I'd be adding a timer to stop grid heating at peak spot prices. You could top up in the lower cost wee hours, and same in the daytime PV generating periods to cover evening showers

The more timeshifting that can be done, the better for solar PV, and also for solar HW

I had considered that. So basically additional costs for automation that Joe public won't ask about while signing up to this awesome freeeeeee deal :)

MikeAqua

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#2016668 16-May-2018 09:53

tdgeek:

MikeAqua:

The other issue with SHW is wind. Performance drops dramatically when the wind is blowing. Even those light Southerlies in winter have a noticeable impact on heating.

Due to cooling of the tubes? Never thought of that. I believe the tubes are encased in a Glycol type of liquid that stops freezing, they also seem to insulate a bit too, annecdotally. I might test the wind effect, although that will be quite unscientific.

Yes. I noticed the effect at our place in Nelson. On a windy day the tube temperature would drop dramatically. Especially in winter.

Mike

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#2016830 16-May-2018 13:47

MikeAqua:

The other issue with SHW is wind. Performance drops dramatically when the wind is blowing. Even those light Southerlies in winter have a noticeable impact on heating.

Not for every SHW system.

We find that wind speed and low air temperature have much less impact than overcast skies and rain. Our evacuated tubes have low thermal transfer so the primary heat loss is at the collector manifold and the pipes that go to the storage cylinder. When we did some research over a decade ago, the best efficiency/performance comes from having the collector surface flush with the roofline and all parts and pipework under cover.

The wind is likely to have much greater impact with the following factors which my system doesn't have:

no vacuum in the collector plate (most tubes are evacuated).
passive circulation so heat capture is usually slower
exposed storage tank
collector raised above the roofline

The second to fourth factors are features of the SWH installed on new Housing Corp houses in my area. So they will be much more susceptible to wind chill.

Aredwood

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#2017260 17-May-2018 01:27

Hammerer:
MikeAqua:

The other issue with SHW is wind. Performance drops dramatically when the wind is blowing. Even those light Southerlies in winter have a noticeable impact on heating.

Not for every SHW system.

We find that wind speed and low air temperature have much less impact than overcast skies and rain. Our evacuated tubes have low thermal transfer so the primary heat loss is at the collector manifold and the pipes that go to the storage cylinder. When we did some research over a decade ago, the best efficiency/performance comes from having the collector surface flush with the roofline and all parts and pipework under cover.

The wind is likely to have much greater impact with the following factors which my system doesn't have:

no vacuum in the collector plate (most tubes are evacuated).

passive circulation so heat capture is usually slower

exposed storage tank

collector raised above the roofline

The second to fourth factors are features of the SWH installed on new Housing Corp houses in my area. So they will be much more susceptible to wind chill.

I also have solar hot water tube type panels on my roof. Even when the water temp in the panels is well over 60deg, if you touch the outside of the tubes, they feel cold.

Interesting about that research on tube installation. As I installed mine on a frame, so they point to true north, and angle is the same as the latitude for my location. The frame needs some repairs, so you have given me a good excuse to get rid of the frame and move the panels directly onto the roof.

Aredwood

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#2017267 17-May-2018 02:23

Krullos:
According to their Agreement:20 Year Value Proposition:
You will save money every year
during the 20 year term of this agreement, and if for some
reason you don’t, we will refund you the difference based on
your pre-solarZero retail energy plan costs (adjusted per
published MBIE quarterly regional electricity price movements),
total energy consumed (including consideration of 5% energy
efficiency gains) and the sum of solarZero Monthly Payments,
less any refunds made and Retail Service Provider payments,
excluding any late payment penalties.

You haven't considered the effect of the sentence I have bolded. Which means that if power prices drop, or there is a change in the tariff structure that wipes out your savings. You cannot claim on the guarantee. As they will simply say that you are still saving money compared to before you had the solar installed.

Imagine those price changes meant that your monthly power bill would only increase by say $50 per month if you were to remove the solar system. But you still had to pay rental fees for the solar system of say $90 per month. You would be loosing $40 per month. But as long as your overall monthly fees are still lower than what you were originally paying. You are stuck with the losses.

Funny how the solar company doesn't want to take on the risk of power prices reducing. As that implies that they think it is likely that power prices will reduce in the future.

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