Solar Interest and Selling Power Back

[workinonit]

As we reach retirement age we are becoming more interested in solar power to supply our home. I've read a lot on here about solar power and many of you guys incorporate solar at your homes. I'm very interested in opinions and experiences. If I decide to go this route, I want a system large enough to handle my entire place and the ability to sell excess back to the power company. The systems it appears I will need look to be in the $30K to $50K range. 13 to 20 KW. I can easily install the system and commission it so there's that savings. I would fabricate the solar panel structure as well. So really all I need is the components. There is obviously the question of payback and at $200 to $300 per month in current power bill I'm thinking at least 10 years and probably closer to 15 if my numbers are correct. I have no interest is signing a contract with a 3rd party to install this stytem. So here are my questions:

Am I in the ballpark price range for what I want to do?
What equipment will I need for what I want to do?
Are the solar panels, lithium batteries or inverters going to be shot before I make payback?
Do I need to incorporate drives to tilt the solar panels for optimal position?
Anyone that has gone this route, where did you purchase your package or did you purchase a la carte?

Thanks,
Randy

 

[Roric]

First off, your milage may vary from mine.
Second, things are 'variable' in the solar market right now.
Like with today's new cars, prices may be 'harder'.
Third, it is good to do your homework, check and doublecheck:
Your electrical utility requirements,
the local codes and zoning,
NEC (electrical code) compliance,
site applicability,
tax advantages, (next year they are back going up).

Here is how it worked for me:

Three years ago I installed a 7.5 kilowatt system on a detached
building. I had spent years pondering it. I had spent the better
part of a year dealing with our utility, local and state zoning
regulation. The hardest part was compliance with utility requirements.

The system was a grid-tied kit from Wholesale Solar in California.
(It has had a name/ownership change since then.)
20 375w mission solar panels
7600 watt Solar Edge inverter with EV charge port
DC Optimizers
Iron ridge mounting rails and support hardware
Inter-connecting cables for DC solar output to inverter.
Static (non-tracking) roof mount 19 degree pitch south facing.
Kit was about $9,700. Added costs for permitting, trenching,
condiut wire and more brought the total to $14,000
After Sales Tax break on solar materials and
after the tax credit (deducted on the next years taxes):
Total net cost of $9400.

I did the install. I did get assistance getting panels on the roof,
pulling wire to the house. (Son, son-in law and brother) The work
took 3 and a half weeks.

Since going online:
Generating 4kw (9:50 am, clear blue sky) right now.
660 kw hours for this calendar month so far
25 mega-watt-hours since in service.

We have had small bills some months, some months with a credit,
(we are in central Minnesota)
and at the end of the year we have come out ahead. It takes
the electrical bill largely off the table. Electrical rates and
charges keep going up.

Wish you the best of luck.

regards,
R

 

[Roric]

Take a look at grid tied kits on North Arizona Wind and Sun.

 

[ponytug]

Great advice above; I would also double check what your utility is willing to pay for the power today, but also how soon they can change that. Here the utility gets to apply for pricing changes on a rolling basis, with about a one year lead time. Despite assurances to the contrary, here, they have altered the buy back rates, decreasing it to wholesale power prices, and appear to be heading for spot pricing (which goes toward zero as lots of solar power gets generated at the same time on a sunny afternoon.

My point being, installing solar is great for your energy independence, but I wouldn't bank on it being a reliable source of income in the future. I would think about adding a battery or two so that you could have power in the event the grid goes down, e.g. after a storm.

All the best,

Peter

 

[workinonit]

Thanks guys. Just the thing I was looking for. Issues and traps. This idea is definately in it's infancy so it can and will change. Selling back excess power would be great, assuming my coop even buys it back. I have a call in to the engineer now. My concern would be a zero power bill if possible. I asked my coop today when I went by to pay the bill about their solar programs. The only thing they have which I had never heard of is for the consumer to buy x number of panels in their solar farms with their devalued output going toward your power bill. I have zero interest in this. No benefit whatsoever for me that I can see. Still a lot of research to do before I pull the trigger on this.

 

[techman]

One key factor is your utility. Our utility offers net metering, which means that you sell at the same price as you pay. In effect the meter runs backwards. However when I was researching putting my 9.2 KW system, the utility offered net metering only up to 10KW installed. At 10KW and above you were treated as a generating plant and excess was paid at the going generation rate, which is quite a bit lower than the net value. That in mind I limited my install to under 10 KW (I believe today that the utility has raised the threshold above 10 KW, but I do not know what the current level is today). If I supply more than I use on an annual basis they will pay me once a year for the excess supplied. I, of course, have never had that happen. Our 9.2 KW generates about 66% of our usage on an annual basis. I did the total install myself (with occasional help from friends), and my break-even was 6.5 years. Bear in mind that when I did the install, everything was much more expensive, panels, racking and inverter. Today the cost would be about 50% of what I paid. One other source of income is Solar energy credits. I get about $40/Mwh (usually per month) from SRECTRADE.com. You would need to investigate availability and rates in your area.

paul

 

[MossRoad]

Man, it’s not just your local utilities, it’s also your state. Be sure and check everything thoroughly before you make any purchases or sign any contracts.

For example, my home state:

Indiana solar net metering rules go from bad to worse | Energy News Network

Changes being ushered in by utilities go beyond what the industry had been bracing for in the wake of a 2017 law that gutted net metering in the state.

energynews.us

 

[MossRoad]

Setting the Record Straight about Solar Net Metering in North Carolina - SACE | Southern Alliance for Clean Energy

This blog post was jointly prepared by the Southern Alliance for Clean Energy (SACE), Vote Solar, and the Southern Environmental Law Center (SELC). Shedding Light on the Proposed Next Generation of Rooftop…

cleanenergy.org

 

[5030]

Michigan is the same as Indiana. No get rich quick on solar panels here either.

 

[MAX-24-Dean]

A good reference for Kwhours produced per year at link below. Just enter the town nearest your location, add DC system size in the box and the application will calculate power production for a year.

PVWatts

Estimates the energy production and cost of energy of grid-connected photovoltaic (PV) energy systems throughout the world. It allows homeowners, small building owners, installers and manufacturers to easily develop estimates of the performance of potential PV installations

pvwatts.nrel.gov

An 8Kw solar array will produce 11,000 Kw hours in Scranton, South Carolina annually.

I Entered 8Kw based on your dollar amount minimum of $30,000. This would pay for an off grid (or hybred offgrid/grid tie system) 8.5Kw solar setup. Would include inverter, batteries, charge controller, combiner boxes, Solar panels, Wiring, conduit and Solar mounts for the panels.

Complete system.

Payback on the system obviously depends on cost per Kwh and if you have higher time of use rates in the evening.

 

[herm0016]

we just installed a 10.8 kw system. total cost installed is about 23k which includes a propane generator backup source as well. about 20k for the solar. Canadian made panels and microinverters. just waiting for the the go ahead by the utility to flip the switch. we got a low interest loan 1.99 % apr 25 years, its about 100 bucks a month as long as we put the tax credit back on it next year. this makes ouR power cost constant for 25 years, then near 0 hopefully. I do not think rates will go down, so we should be ahead very quickly. our power bills are between 90 and 150 per month.

 

[shooterdon]

When I looked into it, it was a loser. Your situation may be different.

One thing to consider. Do you spend $25k to get to 100% of your needs, or $15k and supply 90% of your needs?

There is a point of dismissing return.

 

[orezok]

The utilities are playing a scam. Individuals built mega watts of generation at their personal cost. The solar generation saved the utility from building a Billion dollar generation plant and associated distribution. Now they want to take possession of the individuals solar output. for their share holder gain. Quite a scam.

 

[workinonit]

I agree to some degree however I know that solar power doesn't enter into any load demand calculations the power companies use since loads are based on peaks and for the most part solar is irrelevent at peak times. But I do agree that power companies are taking advantage of the customers on many fronts. The one thing I think power companies are concerned about with solar is the lack of VAR load control on the grid. It's something that doesn't get talked about and is as important or in my opinion more important than MW load. NERC requires them to strictly control VAR load on the system. New voltage regulators that we install today have to be equipped with PSS or power system stabilizers so that regulators don't initiate rolling blackouts in the event of a grid upset. With solar having no real active voltage control the grid voltage must be offset by the large units the companies have on the grid. As more and more solar hits the grid this becomes a bigger issue.

 

[Roric]

Regarding var on a solar install:
It appears that the solaredge inverter I use is correcting the PF power factor I am seeing.
Does var and related power factor specifications fall into required specs for inverters put online?

regards,

R

 

[MossRoad]

I think if I was going to install solar, I’d want to be able to store it myself, and use it from that battery, then only use grid power when the batteries were depleted. That’s due to the way our state has limited net metering, in that it won’t provide the grid as your battery economically.

And, unfortunately, the in that type of system, the return on investment is too long for me.

I’d be better off spending less money than a solar system and super-insulating my house, replacing the windows and installing new, efficient HVAC.

That’s my situation currently. May not apply to others.

 

[workinonit]

Actually, it is against NERC regulations for any generator to incorporatye VAR control. If a regulator is using VAR for control the result of a grid upset has the adverse effect on voltage. Therefore all excitation systems must be designed to control soley on voltage. More voltage, more VARS, less voltage, less VARS. Any excitation system that is installed now must have a PSS if it is above a certain MVA rating. I would think the solar inverters would have some sort of voltage control but likely nothing that can be tuned for stability.

 

[workinonit]

Moss, that's what I am trying to discern. I'm thinking just a stand alone for my consuption or do nothing at all.

 

[5030]

Applies to us as well. ROI is way too long for this old man. At least in our situation, the utility gives us a large break in electric cost for our HWH and if we had a heat pump (we don't), that too. We have 2 separate smart meters, one for the house and one for the HWH. Bottom line with any of it is, it's going to cost you more and more for electricity as well as NG (and propane), nothing you can do about it except turn the t'stat down in the winter or up in the summer or go to alternative fuels like we did for heat. I heat my shop as well as the house with bio mass. The house still requires the heat plant on very cold days but the biomass stove handles it quite well most other times and the one in the shop is always able to maintain the temperature in there.. I have an overhead, high efficiency propane heater but I rarely use it.

I'm in kind of a unique situation as my biomass fuel (seed corn) I get for free so my fuel costs are negligible. I do mix in processed wood pellets with the seed corn at a ratio of 1 of pellets to 3 of corn and there is the issues of loading the units, cleaning them weekly and dumping the ashes but it's still way cheaper than relying on the utility (electric or in our case propane) for heat. Propane is steadily climbing presently. and so is electricity and I think everyone knows why.

Because I'm inherently cheap, I've been heating with biomass for at least 30 years now.

Even considered putting in a stoker coal stove in the house but rice coal around here is hard to obtain where as corn and processed wood pellets aren't and processed wood pellets are supposedly carbon neutral whatever that means.

 

[Roric]

I have been told that I am the only thing getting cheaper nowadays. Whatever she says, I guess.
Here is latest electrical bill:
7.5kw solar array (no battery) average summer with90 degree days and humid too.
I realize we use less than normal kilowatt hours but I have been on a crusade to increase the energy efficiency for a
long time (replaced wall ac with split unit, led lights etc)
On the other hand, we bought a plug in hybrid last year so the demand here is fluid.
The solar production negates the utility supplied electricity so we end up with a credit.
The objective was to take a bill off the table every month.