site prep and federal tax credit

I'd check with my tax adviser.

This site says "Expenditures include labor costs for on-site preparation, assembly or original system installation, and for piping or wiring to interconnect a system to the home." Interpret it however you want, and of course the safe answer is "check with your tax advisor".

Some Federal guideline brochures and websites also state pretty clearly that any preparation with a dual function may not be claimed in its entirety.
For example, if you decide to build a garage with a roof located in the ideal place for a panel array, you cannot count the full cost of the garage.
If you replace your roof because it leaks, probably nothing is covered. If you replace your roof because it was not strong enough to support the panels, maybe at least part of that expense can be claimed.

What if the homeowner adds on another layer of underlayment on top of the existing underlayment (not replacing the existing layer because the existing layer is still good for another 5-10 years and is not leaking yet), only because it'd be more cost prohibitive to remove the panels to replace the underlayment later on when necessary? This is something the homeowner would not normally have to do yet, and only does it BECAUSE of the solar panel installation. Would this be considered single function or dual function? And this is not installing a new underlayment for the whole roof. This is just putting a new underlayment on top of the old one JUST UNDER where the solar panels will go.

I know, I know. Consult your tax advisor is the safe and final answer. Just want to get people's opinion.

For what it's worth, my installer told me that they see many people do this (underlayment add on just under the panels only) and claim it as site-preparation. Not saying that it means it's right or wrong to do. Just saying that I hear people are doing that.

Any C.P.A tax advisors out there care to give free advice ?

I think Bando is a CPA. Hopefully she'll come across this question.

Good subject!

Was wondering the same myself.

thanks for all the advice but there may be another option

So if site prep may be rather expensive, I have a great clearing 300 feet away from the house on 4 acres of land. Is it economically and technically reasonable to put a 12.32 Kw 44 panel array that far from the house ?

thanks!
Guido

A long cable run can be practical as long as you have the inverter in the house and optimize the panels strings to put out high voltage. Probably not a great place for micro inverters.

As for what you can get away with for the federal tax incentive, it all comes down to what you are comfortable with when sitting across the desk of the IRS auditor. Odds are you will never have that meeting but if you do, you have to justify the expenses you claimed and anytime you run into dual purpose issues, they will tend to want to disallow unless you have good documentation. If you need a backhoe to run ditch for the conduit to the distant location, that's probably deductible, if you build a road to the location that might reasonable have other uses you may get kickback.
I would expect IRS has guidelines for solar installs and these use them for audits, $20 per watt you have some explaining to do, $5 a watt probably not.

Thank you

Yeah something I was wondering myself also

​Mod note - forget the links

I have done them as far as 700 feet away from the house.
Just have to keep the voltage drop within reason and put the inverter at the house.

Certainly doable. I have a similar array twice that distance from the house. Running
360-410 VDC is quite efficient. Once inverted to 240VAC your conductor needs
will double to maintain minimum loses for the rest of the distance. Bruce Roe

300 Ft. away

If you're going to be grid tied, I think you're going to do better to have microinverters or a string inverter located at the panels, rather than running a low voltage DC to your house. Losses (and % voltage drop) increase with current and lower voltage means higher current (and losses), for a given amount of power. The only way to overcome the distance at low voltage is to have supersized conductors, which means spending lots of money on copper and oversized conduits. Think in terms of maybe 10X cabling cost at typical panel voltages versus typical AC line voltages. If you make AC power at the panels, you can size conductors based on the lower current and smaller voltage drop, at the line voltage. Once you invert to AC power, you can even choose to step up voltage and then step back down at the house if you have a large enough system.

By the way, if you're ground mounting, you may want to consider tracking as well. You can get an additional 20-30% of power from a given panel investment, with the increased production coming earlier in the morning and later in the afternoon. It becomes an economic trade-off between the increased mounting infrastructure for tracked panels, vs the system output benefit. Tracked panels also do require more clear space, since they pick up sun both earlier and later in the day. Tracking also can have some added operational/maintenance costs, depending on technology selection, so you'll want to look at that as well.

300 ft.

You can go to the higher DC voltages, but that means putting panels in series and protection of DC circuits is more troublesome. For my money, I'd rather not have ~400VDC running across my property. If you connect your panels in series, you do keep current down and elevate voltage, but safety is arguably compromised and a single bad cell (or bird mess) can bring down a whole string.