Hybrid Solar, grid tied solar pv with batteries

[montreid]

Solar Tech with batteries is much more mainstream now. In the past, these hybrid systems were complex and batteries were large and messy. Enter Powerwall and their likes.

Solaredge appears to have bridged that gap to only single inverter need. It's the same inverter they use currently on standard PV and in fact they are upgrade pathways for some of existing PV systems.

http://www.solaredge.com/files/pdfs/preparing_for_storedge_upgrade_on_grid.pdf

So the question that I have is why even have a powerwall system for battery source and a large growing segment is Electric Vehicles? 400k Model 3 preorders is a good start of getting huge batteries available to power-shave between 6p-9p demand loads. Why let that battery just sit in the driveway/garage unused?

I've tried looking for a solution to tie-in our EV, but that's just not out there.

[Mike90250]

But what a mess the loss of power does to the ice cream.

The goo they make modern ice cream flavors does not melt anymore, it's mostly just foam and chemicals, so I did not factor the loss of ice cream. But the kegerator would get warm after a couple hours, and that would be bad too.

[gmanInPA]

I agree... Few companies in my region seem to understand, let alone recommend hybrid systems. I suppose that is because as a business proposition, it's not the path of least resistance for the money earned. I too think that the power wall is touted as some grand solution that it's not and many will buy one expecting great things. One doesn't have to look very hard to see the vastly growing market for preparedness solutions. If I were an installer, I'd be specializing in hybrids and generators because there are a lot of people interested and they're often willing to spend considerably - like someone here who recently declared they didn't care if they spent > $20k to have their fridge and freezer run off of solar! Poo poo the financials all you want... If you want to do well, follow the money people are spending.

[ncs55]

I do not see anyone actively pushing hybrids or systems like what I am describing in this thread to people in my area. The people that want a true hybrid have to search to find a company that can actually do it correctly for them. I, on the other hand see the enphase battery storage and tesla walls actively being pushed on to customers all of the time. IMO, these systems are a waste of money for the average consumer, and are being sold to profit solely the installers. And are being lumped in as a hybrid system. I see intentional confusion by the sellers of these systems by comparing the two types when in reality, they are nothing like each other.

[ncs55]

To be honest a system like yours and what I have described does not generate as much profit as just selling and installing grid tie. We do them because we like to do them and are actually loosing money overall. We make money yes, but could make a lot more by sticking with grid tie like everyone else. I would think for you, a few outages a year and what you could potentially loose far outweighs the cost of that system. Yes the combox is kind of weird to me, the AGS has been reported as flawless by him, but he is not relying on his gen as of yet. We have had some problems with both of those and some other issues with battery charging vs grid tie selling and have to trick the XW into a more efficient scenario. They have to be programmed with some degree of thought to work at optimal and we have had to work with the good folks at Schneider to help us get to optimal operation. On that note I have to say that using the 600V charge controller has been a huge advantage over any of the low volt controllers in overall system performance.

[gmanInPA]

I do the same, and it is a worthwhile exercise on many levels. Not as pleasant of a situation with grid-tied

[gmanInPA]

The 122 yr payback was my payback, solely based on monthly savings for having installed such a system. I have a small array.

So let's get back to the original point... people here, by and large don't seem to be patently against all hybrid systems. There is a lot of exhortation to go another route for those with primarily financial goals, and for those who want backup power. For those folks who want backup power, many who could have a generator supply the need are not aware that doing so would be far less expensive, though of course not in every locale.

[ncs55]

No, the one I mentioned is just a person who wishes to be self reliant even without there being grid outages. He has reported actually shutting his main off and simulating outages for extended periods of time so he can educate himself in real world exercises of not having the grid and what he can actually do with his system. Basically choosing to live off grid temporarily.

[ncs55]

I never said to peak shave with the XW, although yes it can be done, using the new SW is the unit for that application. And yes, you can install a generator to provide power, IF you can get a permit for it and prove that your gen is below the required noise DB levels. Try that anywhere in S.D. County and see how far you will get. Most gens out here in rural areas are unpermitted and unsafe in how they are being used by the customer who hacks them into their home. Also a gen will not let you use an existing grid tie system. So your grid tie inverter is useless and has to be isolated from the gen, and you are relegated to burning fuel. That is ok for a few hours at a time. And yes it is cheaper to install, but living in earthquake and fire country, it is not necessarily the best solution. And yes, hybrids are expensive and no they are not for everyone. 122 year payback? For the system I was referring to at 45k, the payback that customer calculated, is around 15 years for him, not factoring any food loss or other losses with no grid. This was calculated and was a factor in his decision to move forward with this system vs regular grid tie. He is net zero, has only the yearly charges as his bill. The payback is usually double or a little more than that compared to straight grid tie. Not as bad as most in here will have you believe and the equipment prices are dropping.

[gmanInPA]

Remember ncs55 - I too am an XW owner and realize those advantages... some were part of my own decision to go that route. But I can also see the devil's advocate point of view - that you can do those things with a good backup generator, and for much less. Believe me, I see plenty of reasons to use hybrid - just none of them purely financial. That is THE main point that many here (including myself) often make, because many looking for such systems approach hybrid systems believing they will save money - whether through ignorance, or because that is how it is sold to them. For my investment of ~$26-30k, I save about $17/mo. That is a 122 year payback at a minimum . That is just my scenario based on my use patterns, the sun in my area, etc - but I really doubt the average homeowner is going to save scads of money. Anything they do save should be banked for their next battery, which they are sure to need. One does save some money on their monthly bill, but they spend a whopping amount to do so, so there is no true savings.

FWIW, Schneider only recommends peak shaving if ALL the loads are on the inverter, which is unlikely on a single XW 6048, especially with an inverter only supporting 60 Amps AC output. You can still do so, and set it very aggressively, but you would not want to do so in a way where more kWH are used from the battery than were put in. Furthermore, when you use peak shaving, you are reducing your battery capacity, so if the power goes out during that time, you're not at 100% SoC - therefore reducing the time until the battery is discharged and reducing the effectiveness of having a battery backup. These aren't things that one really learns about until you start using a hybrid. They can do a lot, but there are always tradeoffs.

Also, if one doesn't understand what they're doing with peak load shaving, they're basically just selling their battery capacity to the grid, which with normal POCO rates is just silly, because the credit earned per kWH sold is a fraction of what it cost to obtain it - at least in most contexts.

[ncs55]

No, it does not physically pay for itself in a week, and that is not what I was referencing that to. That is the value that my customers say to me because in some cases it does to them. Look at it from a different perspective and Consider medical patients who have expensive medical equipment that cannot fail or they can possibly die. Is their life worth $45,000.00? If they have to go into the hospital for a week or two, it could cost close to that. For the preppers that have massive food storage, loosing say two freezers and a few refrigerators full of food can cost thousands if it goes bad, It would be hard to eat it all before spoiling, and several outages in a year would add up. And the type of hybrid system that I am selling and referring to does not compare to the toys like the power wall. The XW system feeds into the grid just as a normal grid tie and they get their credits, plus they can live comfortably if the grid goes down forever. The other systems that you are comparing are temp backup and will only provide peak shaving or 4-6 hours of backup. Not even close to a comparison.

[SunEagle]

I think as has been shown, the general consensus here is that hybrid systems are expensive, finicky and often not the right answer, However for the "house at the end of the power run" and the business that can fail if offline too much,a hybrid system is the best answer, For Joe in the 'burbs, it still works, but it's not going to save him any money, the deep freeze full of moose steaks will keep 6 hours till he starts up the generator.

But what a mess the loss of power does to the ice cream.

[Mike90250]

I think as has been shown, the general consensus here is that hybrid systems are expensive, finicky and often not the right answer, However for the "house at the end of the power run" and the business that can fail if offline too much,a hybrid system is the best answer, For Joe in the 'burbs, it still works, but it's not going to save him any money, the deep freeze full of moose steaks will keep 6 hours till he starts up the generator.

[SunEagle]

My system is primarily for my business. On average, I stand to loose ~$2-3k per business day of down time. That happens approximately 5-7x per year on average, mostly because of vehicular accidents on a nearby highway causing outages, and secondly, due to the weather. Downtime also amounts to frustrated clients who might take their business elsewhere if I'm unavailable frequently-enough. Staying up and running with as little human intervention as possible is helpful to my business. There was also tax benefits for the system.

I enjoy the seamless nature of the battery backup vs the time required for a backup generator to kick on, warm up, and take a load. I could have solved these problems using a whole bunch of cheaper UPS systems and a generator perhaps, but the solar allows me to work entirely off of PV during the bulk of my business hours (when the sun is shining). It doesn't save me much at a POCO level, but there is still monetary value to the installation.

Sounds like you are doing the best you can using the solar technology to keep your business up and running when the grid goes down.

No one likes to lose their electric power but for some it is an irritation, for others it means a loss of business which can run into some big dollars.

Everyone needs to do the own calculations to determine if an energy "backup" system is worth the cost or not.

[gmanInPA]

My system is primarily for my business. On average, I stand to loose ~$2-3k per business day of down time. That happens approximately 5-7x per year on average, mostly because of vehicular accidents on a nearby highway causing outages, and secondly, due to the weather. Downtime also amounts to frustrated clients who might take their business elsewhere if I'm unavailable frequently-enough. Staying up and running with as little human intervention as possible is helpful to my business. There was also tax benefits for the system.

I enjoy the seamless nature of the battery backup vs the time required for a backup generator to kick on, warm up, and take a load. I could have solved these problems using a whole bunch of cheaper UPS systems and a generator perhaps, but the solar allows me to work entirely off of PV during the bulk of my business hours (when the sun is shining). It doesn't save me much at a POCO level, but there is still monetary value to the installation.