Residential Solar Options

[glandpuck]

This is just my opinion.
If you want a low frequency inverter (uses transformers) and is built like a tank, is hybrid and can be expanded in parallel, an Outback Power Radian system will fit the bill. They are very reliable. Their main drawback is they are an ecosystem requiring additional hardware pieces to be purchased and attached to them for full functionality. They support lithium batteries, but not yet in a closed loop automated kind of system. You have to do a little programming. But they will start big heavy motors that have large induction loads. They are only for indoor installation and do best in an environmentally controlled space, not an unheated garage in Toronto.

The SMA and Fronius inverters are made in Europe and are very high quality. I believe they now offer hybrid systems to be paired with batteries. I have older SMA units at my home that have been trouble free for 9 years now.

Then there are the newer inverters coming out of Asia. They vary in quality and features because the space is evolving very rapidly. Service and support for these models also is evolving and may or may not be adequate for you. Examples are Sol-Ark in USA (Deye), Luxpower, Growatt, Solis, etc. There are many more. If you are new to solar, then it is most important that you plan very carefully your entire system design from panels to wires to batteries and to inverter so that you maximize your benefits and are not disappointed in performance.

Make certain plans are drawn up that can be permitted and that you yourself have seen the plans, understand them and have the opportunity to ask questions. Make sure your contractor follows the plans during construction, the system is built to applicable codes and fire safety and can be inspected and pass the inspection before all the money has been paid out (Yes, I watch Mike Holmes on TV all the time).

Lastly, learn how to operate your system as the system administrator because in the real world, contractors come and go all of the time and you are left holding the bag down the road, you want to know how to operate the system.

Lastly, I know hydro is cheap in your area, I know it is rainy and cloudy in your area, I know there has been no Stanley Cup since 1967. There is an excellent company in Toronto called Aurora Generators who you may wish to contact and see if they can help along the way with solar and or just generator backup.

Good luck.

 

[Jman99]

Thanks for the through response! Also.. I appreciate the leafs reference.. ha. It has been painful for quite some time here

 

[Jman99]

For edutainment, please provide a link to warranty terms, and tell us how you see it.

SMA warranties are for a number of years, but the fine print also limits to kWh processed. They used to have 5 year warranties on everything, some now longer standard and some optional to 25 years. They of course have decades of experience to go by. But for new products of new architecture, they have to base costs on engineering analysis.

As years go by, I find equipment on the used market. Also new model MSRP sometimes also cost less. So self insuring makes sense.
If nothing proprietary, you can also substitute brands. For instance, Fronius GT PV inverter could replace SMA. But SolarEdge has proprietary optimizers, so need same equipment to replace.

 

[Jman99]

Don't get optimizers without a reason to get them.

I haven't heard of fire risks with optimizers beyond that intrinsic to adding more connection points. Optimizers tend to include Rapid Shutdown which is required by code on a roof and is supposed to improve safety for first responders.

There's basically only TIGO and SolArk optimizers. The SolArk optimizer are pretty new, I'm not even sure they're on the market yet. They're more complex than TIGOs in terms of the optimization circuitry & algorithm that they have (they have per-optimizer MPPT and I believe buck/boost (drop and raise voltage), while TIGOs do not have MPPT and are buck only. The buck-only design of TIGO interacts with string MPPT in ways I understand better and expect to be broadly compatible with no risks, though note I'm not a product designer in the industry...)

TIGOs have been around for a while which means plenty of people have installed them and posted threads about them. However there's also posts from folks on the forum like TIGOs interacting poorly with AFCI detection on some inverters.

The fact that SolArk are new, plus are more complex/have voltage boost capability, disincline me to using them. On SolarEdge (which is a proprietary optimizer system, with per panel buck/boost and MPPT) there is some magic that the inverter does to tell the optimizers what voltage to converge to. If I was running a solar installation company, sure I would probably do a test install at my office or house. But I just have the one system I install for myself, and I don't make money playing with random stuff.

Err, actually there's another new one, whose name escapes me, that is in the same functionality class as SolArk (per-panel MPPT, buck/boost). One or two threads about that. Also bleeding edge new, and same issues.

I have some shading from trees that may reduce my solar production.

It’s not major.

What would be the reason for not getting optimizers? Every sales person I have spoken to recommends them.

Are they just trying to make more money or is there a huge benefit to having them?

 

[Hedges]

Optimizers can't help a panel that is shaded by a tree. If only occurs with sun off-angle, don't worry about it. But will they grow?
If you have two strings in parallel and 10% of panels on one string are shaded, optimizers won't increase yield.
If 30% maybe 50% of panels on one string are shaded, optimizers should increase yield.
If 70% of panels on one string are shaded, optimizers won't increase yield.
Optimizers might help with panels of different orientation in a single string. While sun angle on them isn't too different.

If you're buy RSD, maybe optimizers don't cost much more. Try to get panel level monitoring, then you can tell installer to replace bad panels (or more likely bad optimizers.) Same goes for microinverters.

Quality panels usually don't go bad. Bypass diodes can, if there are hard shadows when others have direct sun.

If panels can be ground mount so RSD not required, I would not use any module level electronics. But I am putting Tigo RSD on a new rooftop install.

 

[Jman99]

Optimizers can't help a panel that is shaded by a tree. If only occurs with sun off-angle, don't worry about it. But will they grow?
If you have two strings in parallel and 10% of panels on one string are shaded, optimizers won't increase yield.
If 30% maybe 50% of panels on one string are shaded, optimizers should increase yield.
If 70% of panels on one string are shaded, optimizers won't increase yield.
Optimizers might help with panels of different orientation in a single string. While sun angle on them isn't too different.

If you're buy RSD, maybe optimizers don't cost much more. Try to get panel level monitoring, then you can tell installer to replace bad panels (or more likely bad optimizers.) Same goes for microinverters.

Quality panels usually don't go bad. Bypass diodes can, if there are hard shadows when others have direct sun.

If panels can be ground mount so RSD not required, I would not use any module level electronics. But I am putting Tigo RSD on a new rooftop install.

Thanks again. RSD is required for my roof mount.

I’m not sure if you had a chance to review my three options/quotes I posted last. Just wondering if the materials being used are optimal and if there’s anything I should be adding/replacing.

Also which package is best.

Regarding “maple leaf” pannels. I’ve never heard of them. I assume a re-brand. Any thoughts on these?

 

[Danke]

Thanks again. RSD is required for my roof mount.

I’m not sure if you had a chance to review my three options/quotes I posted last. Just wondering if the materials being used are optimal and if there’s anything I should be adding/replacing.

Also which package is best.

Regarding “maple leaf” pannels. I’ve never heard of them. I assume a re-brand. Any thoughts on these?

Those were not unreasonable quotes. If you’re going solar just to save money somethings to think about:

How long will you own the place?

Also, Current usage - amount offset by solar = kW?

multiply that number by your your electric rate. (Any net-metering may come into play)

Then compare cost of solar installation (- any tax credit/rebate?) to your yearly savings.

Also factor in returns on that amount you would pay for installation if it were instead invested (say at 4% in bonds, etc.)

Of course outside of money, reasons to go solar may include security for long grid failures (short ones just use a generator), warm feelings you’re saving the world, or keeping up with the Joneses timselectics.

Anyone chime in if there’s other considerations I didn’t mention.

 

[Danke]

Hedges asked how you electric heat. If it’s resistive heating, you might think about heat pumps. And if you have the land, geothermal heat pumps.

 

[Jman99]

Hedges asked how you electric heat. If it’s resistive heating, you might think about heat pumps. And if you have the land, geothermal heat pumps.

So it’s a bit complicated. We just moved in 3 months ago.

I have three sources of heating:
1. Furnace/natural gas (duct work main level and basement only). Also has central heat pump installed as well.
2. Resistive heating the light the whole house. Basically the only way to heat the two of my bedrooms and the top 2 floors (custom built house).
3. 2 headed mini split: master bed and living room.

As I’ve been learning, it’s quite expensive to heat this home in the winter months.

I’m also planning on adding a heat pump pool heater in the spring.

 

[glandpuck]

"Optimizers" are of 2 kinds: AC and DC. The entire purpose of an "optimizer" is to maximize solar output from an array where part of the array may be shaded by a tree branch, a utility pole or chimney, etc.

Shading does not reduce PV power in a direct manner. If you have 8 panels in an array, each 300 watts and 2 of the panels are shaded by 50 percent output, the array will not produce 2100 watts of power. the output will be reduced by maybe 50 percent or more!

Solar Panels In Shade: Why even partial shading is bad | Solar Choice

Want to know what your options are when it comes to placing solar panels in shade? This guide will explain everything you need to know.

www.solarchoice.net.au

"If it is unavoidable to not place your solar panels in shade, then microinverters or power optimisers might be the right option for you. These devices get around the problem of partial shading by eliminating the need for or importance of strings in the first place. Both microinverters and power optimizers essentially allow every solar panel in a system to operate independently, so that overall system energy production is not disproportionately affected by just one or two shaded panels."

If you use an AC microinverter installed on each panel such as Enphase, each panel is optimized by the MPPT controller on board the microinverter so the total output of power is maximized. AC current traverses from the array to your main panel or the grid tie.

If you use a DC optimizer like Solar Edge, the optimizer is installed on each panel and the DC output of the panel is optimized separately from the other panels in the array and then sent to the inverter.

In either case, there is an optimizer on each panel. If your panels are easily accessible for service or going to be free from storm damage, then this works well. If your panels will not be easily accessible such as a steep or slippery roof or a high wind area, maybe you don't want the cost of these optimizers in that location. In that case, a good MPPT charge controller is the choice.

As for the top 2 floors of the home, maybe there is a way to run Pex and hot water circulation heating rather than resistive or even a minisplit.

Now, onto the heat pump for the pool. I say no. Heating water takes a lot of energy. The current heat pump pool heaters by say Raypak are only about 160K BTU. We in So Cal. Our ambient water temp in the summer hits 82 degrees. We have about 35,000 gallons with pool and spa. Our LP heater is 399,000 BTU! That's to heat water about 10 degrees or spa to about 102! In conclusion, heat pumps are not ready for heating a pool. Neither is solar on the rooftop. If you want to enjoy your pool and spa, just get a good natural gas pool heater of the right size and enjoy it. Otherwise, I think you may be sorry.

 

[k490]

These videos suggests that optimizers are not more effective than the panels built in bypass diodes.

Part 1

Part 2

 

[Hedges]

That is what I would expect, although I haven't used them.
I have experimented with selective shading a 9s2p array (diodes appears to allow nearly all available power.)

I think the optimizers could help with somewhat greater percentage shading of one string out of some parallel ones.

I suspect they will perform better with those silly "half cut" panels where partial shading cuts current in half. That is, if optimizer can do 2x current boost.

 

[zanydroid]

Regarding “maple leaf” pannels. I’ve never heard of them. I assume a re-brand. Any thoughts on these?

No clue, you'd have to ask around in Canadian circles. They're also rebranding the LuxPro. The specs on the battery are also very close to the PowerPro from EG4.

Have you confirmed that which of these will give you a fully code compliant install including the ESS? If they're able to use the listing certs that EG4 uses for the inverter and 14kWh battery then it probably would be.

As for optimizers. If it's not major shading, then the question is around monitoring. I think there are lots of overseas installations that are optimizer-free with the same kind of minor shading, so it probably is not a big deal for the bypass diodes. My guess it's an extra $800-1200 over RSD only modules. The monitoring will mostly help debug installation issues and if things break in the future.

So you get three buckets of value:
- Longer panel lifespan from less bypass diode activation. (they likely don't care about this outside of north america where RSD and optimizers are rarer)
- Slightly more harvest when shaded
- Easier debugging for installer/future service. Keeps them honest -- you can post the numbers collected by modules on the forums and people will help you debug.

Basically the only way to heat the two of my bedrooms and the top 2 floors (custom built house).

I would suggest putting some energy meter channels on all baseboard / resistive zones to see how much they're drawing. And don't drop $40K without a full picture of the cost/benefit of converting these to HP or whatever. Emporia Vue should be $300-400 installed.

 

[DIYrich]

Not sure about this. I see compatibility letters countersigned by both companies for RSD-only but a lot of official workaround & workaround threads for using a CCA.

SolArk did recently change some stuff for their RSD transmitter, maybe to prepare for their own optimizers.

https://www.sol-ark.com/wp-content/uploads/2023/03/TX-15K-A-SPECSHEET-1.pdf

 

[zanydroid]

https://www.sol-ark.com/wp-content/uploads/2023/03/TX-15K-A-SPECSHEET-1.pdf

Doesn't say TIGO in there.

I don't believe TIGO has settled their lawsuit with SunSpec either, that I believe prohibits them from interoperating with SunSpec RSD (theoretically possible because both are PLC-based)

I see only reference to "SolArk O900-80V or any other SunSpec RSD Certified"

SolArk O900-80V has superior optimization capabilities to a TS-A-O. Has MPPT, buck-boost, and can do 2S of panels if they're small enough cell count (if my math is right 2s of 54 cell would be fine in place that don't get much below 0C). None of those available on TS-A-O. So it's not a Tigo unless Tigo is giving Sol-Ark more MVP support than their own product line...



As well, this is PLC-based system (IE SunSpec and TS-A-F) and CCA/TAP (what you need for TS-A-O) is wireless. So this module can never be made compatible with TS-A-O. See the green waves? Screenshot from Tigo manual

 

[foggysail]

Hedges asked how you electric heat. If it’s resistive heating, you might think about heat pumps. And if you have the land, geothermal heat pumps.

Land requirements vary considerably depending on the type of heat source. A vertical well needs almost none. I am doing my research now and I intend to have something started by summer. I want to go geothermal but if I cannot get there ($$$$$), I will go with air that I believe sucks. I have yet to find an air system claiming to work to minus temperatures that will post their COP as a function of temperature. Below 40F, is questionable.

 

[zanydroid]

Land requirements vary considerably depending on the type of heat source. A vertical well needs almost none. I am doing my research now and I intend to have something started by summer. I want to go geothermal but if I cannot get there ($$$$$), I will go with air that I believe sucks. I have yet to find an air system claiming to work to minus temperatures that will post their COP as a function of temperature. Below 40F, is questionable.

Look on neep.org. A full website dedicated to COP and capacity vs temperature.

Plenty of ASHP that work to full name plate to 0F. COP will take a nosedive though.