To pull the trigger or wait, new solar PV

GW

I shelved the idea again, I'm kinda disenchanted with the payment terms,

(just a tad under) 1/3 upon signing,
(just a tad under) 1/3 upon start of job,
(just a tad under) 1/3 upon finish of job,
and a small $1370 upon activation.

I don't put out my hand until we are there on the job working, and the other hand goes out when the system is up and running. What a huge difference in terms.

Brewbeer

I, too, was disenfranchised with the payment terms, which looked almost exactly like yours. Felt there wasn't enough "hold back" at the end while you are waiting for the electric company to issue the final approval to begin operating. I brought this to the attention of the company that I contracted with, but they just offered up some empty comments. I suggested that the third and fourth payments be switched, they didn't go for it. But I wanted to get into their schedule and get installed so I could capitalize on the best power production time of the year: spring and summer.

D107

Those are horrible terms, makes you wonder about the company's financial stability if they need to commandeer piles of cash like that. Company I'm looking at--which negotiated a deal with our municipality--requires no payment until 30 days after job is done if you take advantage of their loan with no interest or a year. This loan will cover 2/3 cost of job to be later covered by fed and state tax credits. The issue for me--aside from what I've mentioned earlier in thread--is what is the 25-year parts and labor warranty worth; If company or manufacturer disappears there's really no recourse.

Fred

@David107 , You can pretty much bank on these companies not being around over the next 10 years. They'll be nudged out by larger companies or availability of parts for the products they are selling today won't be there and they want to sell you some type of upgrade with a nominal credit for the failed part/system. You just have to figure out the break even point, which from what I've seen appears to be about 8 years and decide if you will still be there to start to get the real benefit or hope to get another 10 years of useful life. add something in your analysis starting around year 5 for service/maintenance.

Leonard

I'ld look into paying by credit card. Some cards are supposed to have guarentees in them, that the thing you buy works. Don't know if that applies to contractor work though. But seems it should to the equipment. Talk to card co.

In addition I'ld write into the contract that the contractor guarentees the system works and will be accepted by the utility, and meets all applicable building codes. Seems this will set the basis for defective goods (not as advertised) when you make a claim with the card co.

GBart

off topic but -
Has anyone noticed that since 2008 and the push and expansion of solar pv especially for factories and corporations that we have not had a low volt or brown condition on real hot days?

hot_rod

Adding PV and solar to the grid does help those peak load conditions somewhat, although not an ideal on demand source like the NG peak shaving plants.

Texas is number 1 in wind power and may take over the #1 spot for PV this year. In 2016 wind provided near 12% of Texas energy.

nibs

Chiming in on an older thread, the discussion of efficiency is off base.
The criterion should be cost effectiveness. Since the energy source is free, why would it matter if you only capture 1% or 70% of the energy. Cost benefit analysis decides if the installation will pay for itself, this depends on the amount of insolation (Sun energy), the cost of the panels and mounting, the potential for buyback, the local electricity metered cost in your area, etc.
Panels are not going to increase in efficiency very much unless there is a breakthrough in the type of cells, costs will come down only a little as the panels are already priced at a "commodity rate".
The biggest change is the cost of small 'grid tie' inverters these now can be had for as little as $100/KW. Have used PV panel(s) since 1980 and have lived essentially off grid for a total of about 14 years since 1980, full time sailing and rv ing.

Zman

The efficiency conversation is valid in some contexts. If you were to compare hot water solar to PV solar without government subsidies, hot water would win out due to higher efficiency.

nibs

The two are only related because of the energy source, the valid consideration is .... what is the cost benefit analysis of PV.
Just the same as ....what is the cost benefit analysis of solar HW.

hot_rod

The challenge with thermal is finding a consistent load for it, not a lot of summertime load for thermal heat, or DHW on residences.

Brew Pubs and a few other high water use buildings may still pencil out.

Zman

hot rod said:

The challenge with thermal is finding a consistent load for it, not a lot of summertime load for thermal heat, or DHW on residences.

Brew Pubs and a few other high water use buildings may still pencil out.

Don't forget swimming pools. Very big battery.....

GW

I feel like the nut was just too big. I was looking at a 30k ground mount, so maybe 20k after incentives. That’s still 12 years of so worth of electricity. I fear I do t have the faith that the system won’t require expensive servicing costs over the years.

Case in point- how many dilapidated thermal solar systems are there still clinging to old beat up roofs from the 1980s? The solar people seemingly vanished after the tax credits went away

hot_rod

If you really want solar PV you could totally do that install yourself. Hire and electrician for the wiring and tie in, permits etc.

Modules are available for under a buck a watt now, way under for no-name brands

18- 300W modules would get you 5.4KW. Rebates still apply if you do the install yourself, I gave all the invoices to my tax preparer when I put 1.5KW on my shop.

I used micro inverters on each module, all it required was a #10 wire from the modules, thru a disconnect into the breaker box. The utility installed a digital power meter to record any feed in for credit.

Gordy

Still to inefficient in the conversion of energy.

15-21%....... that’s a lot of extra square meters of area needed.

Yes it’s all we have now, or shall I say all they’ll give. The technology for higher efficiency is there. Probably way higher than we even think.

It’s like technology. Pay high dollars for the latest greatest this year to only pay the same, or less for more technology in the next year or two. I’d hold off.

NY_Rob

^ Agreed, the good news is that when yesterdays "latest and greatest" becomes second best next year it can be had at reasonable prices.

My buddy's 2016 system needed 43 315 watt panels to generate 13,545 watts.
My 2018 system uses 40 335 watt panels to generate 13,400 watts.

I have 3 less panels, generate the same wattage... and my system was about 3K less expensive.
All due to 2 yrs of progress.

hot_rod

Wait how log? At what conversion % would it be the time to go PV. Experts say not to expect huge gains going forward, a few % now and then. Same with cell phone technology, it has slowed from the earliest models.

Pricewise, could it go much lower? 50 cents a watt? 25?

At some point I want the product badly enough that I'll buy knowing full well it will improve somewhat as years go by, computer technology for example.

Now with solar thermal, not much has changed, as far as efficiencies. Some insulation improvements. If anything the thickness of the metals has decreased and I wonder that modern panels will see 20 years or more.

I still have a Revere solar, circa 1978 on one of my roofs. The copper absorber is so thick I can't even cut it with a tin snips. The new ones you can rip the copper with your fingers

i

nibs

Will repeat what I said earlier, conversion efficiency is not a realistic metric for solar power, the only real consideration is cost per watt of usable energy.
In some areas PV is cost effective in some areas it is not.

D107

Keep in mind that, at least Con Ed in NY, residential--and maybe commercial too (I'm on vacation now and can't fact check) the utility will cease giving credits for power generated by the user but not used and temporarily stored by the utility--for all solar systems installed after 2019. That means that after that date the customer will have to install some kind of backup battery to store that power. Those that DO have their system installed by 2019 are grandfathered for 20 years under the present system of utility credits.

Not sure of the efficacy of the battery systems but they will cost. Find out your utility's plans for your state.

NY_Rob

David107 said:

Keep in mind that, at least Con Ed in NY, residential--and maybe commercial too (I'm on vacation now and can't fact check) the utility will cease giving credits for power generated by the user but not used and temporarily stored by the utility--for all solar systems installed after 2019.

That's terrible for consumers if true and could literally kill residential solar installs.

There's literally no time where panel output matches consumption. You over produce in the summer and under produce in the winter.... the only thing that gets you anywhere close to zero at your anniversary day is "banking" and later "withdrawing" from the POCO.

Sal Santamaura

NY_Rob said:

...That's terrible for consumers if true and could literally kill residential solar installs...

Which is precisely the goal of electric utility companies nationwide.

hot_rod

NY_Rob said:

David107 said:

Keep in mind that, at least Con Ed in NY, residential--and maybe commercial too (I'm on vacation now and can't fact check) the utility will cease giving credits for power generated by the user but not used and temporarily stored by the utility--for all solar systems installed after 2019.

That's terrible for consumers if true and could literally kill residential solar installs.

There's literally no time where panel output matches consumption. You over produce in the summer and under produce in the winter.... the only thing that gets you anywhere close to zero at your anniversary day is "banking" and later "withdrawing" from the POCO.

It really depends on how the array is sized. Unless you plan on living 100% off grid, it is rare to find a system that will provide 100% of the homes needs, probably not enough roof space on many homes for that size array. Energy management is the key.

If the home or building has AC, much of a 5K array could be consumed just conditioning and running appliances in summer.

In winter months, typically a lower solar fraction, a heat pump or electric boiler would assure you use all the array could produce, in daylight hours anyways

Germany pulled back the FITS, feed in tariffs, so some of the controller manufacturers now build PV dump control that sends any excess PV output to thermal load, DHW, hydronics, etc. Use as much or all the array output before "giving" it back to the utility.

NY_Rob

Here's my Generated kWh vs. Usage... not being able to "bank and withdraw" from the POCO would kill me....

In order to not overproduce in the summer the smaller system wouldn't even come close to matching usage the other six months of the year.

Brewbeer

In my area, the POCO charges about $0.21 per kWh when I use their power, and they credit me about $0.09 per kWh that I generate but don't consume. Battery storage technology is still too expensive to make it cost effective in just about any area served by the grid.

hot_rod

NY_Rob said:

Here's my Generated kWh vs. Usage... not being able to "bank and withdraw" from the POCO would kill me....

In order to not overproduce in the summer the smaller system wouldn't even come close to matching usage the other six months of the year.

That is everyones challenge with solar, the winter months just don't have a lot to offer.

Move to a warm sunbelt climate with 350 or more days of sunshine and consistent loads

D107

Yes up until a year ago or so there was an anniversary date at which time the utility would zero out any excess solar-generated kwh and apply the credit towards the bill--i believe at a lower rate than what the consumer payed for electric. For the consumer the best way to make that work was to make sure your anniversary date was when your surplus kwh 'bank' would be at its lowest--maybe early spring(?) Some customers, depending on their solar install date are still grandfatherwd in that system though i believe they have the right to change to the system described next paragraph and available until 2020.

Then the utility switched to returning excess generated unused kwh in kind at a 1:1 ratio which seems like the fairest way. For me, the only way to explain the upcoming change is that the utility fears losing revenue lost to solar panels.

Dumping the excess kwh to hydronics may be the only way out except one would have to calc how much the hw load could use of that excess.

I decided not to get solar panels installed due to the installer and manufacturer location being too far away for timely repairs and other reasons. Our town joined an energy cooperative esco along with other municipalities that was able to bargain for lower supply rates for wind-generated electricity which should save us about $125 a year and be green in the bargain. I've also looked into community solar which is coming into its own.

jumper

nibs said:

Will repeat what I said earlier, conversion efficiency is not a realistic metric for solar power, the only real consideration is cost per watt of usable energy.
In some areas PV is cost effective in some areas it is not.

Correction: it's cost per kw-hour.

Counting on utility buying electricity when you don't need it is a gamble.

Cheapest (and most efficient by some measure) method of energy storage is hot water. How many kilowatts do you need to produce one therm per day?

hot_rod

Entry level$$ solar. Great for solar demo at schools.

I put a lb. of frozen ground beef in it at 10:00, by 4:00 it was cooked and browned. A batch of brownies, about 2 hours.

Lots of choices here:
http://www.solarcooker-at-cantinawest.com/solarcookingclasses.html

Gordy

I think if I was going to do it I’d go all out with an Elon Musk system. Kill two birds with one stone. I have admiration for him at least.

Leonard

I'm on a generator website. Lot of people use gens for power during utility outages. Gen are fuel thristy $$$ over few days. Adds up if frequent outages.

Since have all this solar equipment would be nice to use it to power your house during utility outage, Guessing cost is not much more over micro inverter.

Instead of micro inverter on each panel I'ld lean towards bringing solar panel DC output down to one main inverter. Buy a type of inverter that you can turn a switch to isolate it from the utilty power and power the house. This would satify legal requirement that can't back feed into street utility line if utility line is dead. (lineworker safty issue)

As I understand it can't do this with micro inverters, because they currently have that utility power sensing "feature" built into them.

Likely would need as least some type of minimal bat storage so voltage doesn't drop or shut off every time a cloud passes. Don't want system to saulute every cloud.

nibs

Only so called "grid tied" inverters need grid power to work. most inverters do not.
Your biggest requirement will be sufficient batteries to store the power needed to run the system.

Leonard

Grid tied ...... yes grid tied inverters are special...... if your feeding power to grid then laws requires you stop feeding grid if grid goes down, so they contain additional circuits to do that . Generally inverters don't need grid to make AC

Batteries typically store a NOTORIOUSLY small amount of power unless they are huge or have a lot of them.

I was thinking of just a few bats for a very short backup, ~ 5 minutes maybe. So if grid power is out you can have power for a few lights and computer and system doesn't shut off ( saulute) every cloud that passes by. Obviously you can add bats for longer backup

GW

I'm sure AOC will figure out a way LOL

NY_Rob

Supposedly the recently announced Enphase IQ8 Microinverters are "Grid Agnostic" and will be able to use PV power for your home when the grid goes down.... and without the need for storage batts. Of course without storage batts the available power supply will be affected by passing clouds and sundown. But, if your power is out for a few days after a hurricane, storm, etc... I could be a great advantage to have PV available at your home.

https://pv-magazine-usa.com/2018/08/20/enphase-going-einstein-with-iq8-solar-power-inverters/

Leonard

Next step would be for the system to automatically shed loads as passing clouds shade array. Might allow some "priority/critical" loads to stay running. Ei shut off or throttle back a resistance water heater.

JerryW

Hi everyone, I'm about to buy hotel in Germany https://tranio.com/commercial/germany/adt/1747272/ I found this great listing a month ago but I have some hesitations. The problem is the previous owner of the hotel said that he was using a solar system for saving some money from the bills in addition to the usual systems but I'm not sure how much efficient it would be. So now I'm thinking about changing the old solar panels to new PV but if it won't pay the expences for itself in the short term I don't wanna do this not to lose money. Any ideas?

nibs

No need to throw out the existing panels if they are producing power. Just add new panels to bring up the output to what you would like to have.

hot_rod

Assuming you are talking about solar PV not solar thermal?

Pay attention to the change in the FITS in Germany. Public pressure has forced them to cut way back on the feed in tariffs, as ratepayers were complaining they all were paying for the buildings with solar, an unfair reallocation of rate payers $$.

So look carefully at the numbers they crunched for energy costs as it is crazy expensive in Europe and could be a big number in a property like that.

They have cut back on wind development a bit also as their aged grid was un-able to shift the energy from the wind farms to the areas it is needed.

Leonard

Interesting apparently you only get the hotel, not the land. 20 year lease with two 5 year options. I see trouble down the road, what do you do in 20-30 years. Be forced to sell at a loss if the economy is down at that time ?

Funny that the notary gets 1.5% ....wish they had that pricing here , I'm a "justice of the peace" ( notary public). I'll notarize your signature

jumper

If you have the room and the know how; the best return on solar is off grid. Money for stuff and service has to come from somebody.

That means something like ten kw capacity and 600 kwhrs of storage? Say $50,000 investment? Spare yourself $2,000.oo per year electric bills? That is 4% per annum after tax. Pretty good right now. How long will PVs last? If batteries need to be replaced after ten years you lose money.

If PV plus storage pays businesses would be doing it already. The electric utility business involves financial engineering. We can't do likewise for ourselves.