Request for input on solar proposal - Q Cells and Enphase Microinverters

[Ampster]

When spending money on personal residences or vehicles for transportation the term "utility" comes to mind. Whether it is functional utility or cost savings those type of expenditures are always subjective.

[mjs020294]

If you're on the fence about solar and it's ROI, have you remodeled any perfectly functional rooms in your house? There your ROI is "it feels good/looks pretty, etc." I'm putting solar on my house and at 65 my ROI looks to be 8-9 years, but it will be pretty to look at and, in the meantime, and will more than halve my electric bill.

Although solar might pay for itself with a simplified calculation once you factor in finance charges and/or lost opportunity costs solar rarely truly has a positive ROI. I had a Sunpro sales guy go through his pitch and with basic calculation and assumptions that favored the seller and my savings over 25 years were around $80,000. I told him if I took my $30k and simply put in the S&P 500 it would be worth around $260,000 in 25 years time. It gets worse for solar when you consider in the south shingle roofs rarely last much longer than 20 years, even assuming you keep the house that long.

Like others have said the true savings of solar are unlocked when you go EV. Electric motors are about 2.5-5 times more energy efficient than gas engines, and when you generate your own electricity the savings are huge.

[J.P.M.]

If you're on the fence about solar and it's ROI, have you remodeled any perfectly functional rooms in your house? There your ROI is "it feels good/looks pretty, etc." I'm putting solar on my house and at 65 my ROI looks to be 8-9 years, but it will be pretty to look at and, in the meantime, and will more than halve my electric bill.

Aesthetics are subjective, beauty in the eye, etc.. There are actually some people who think a rather large, black monolithic slab on a roof is an eyesore regardless of how it's perceived to improve the looks of their financial picture.

Most folks get residential PV because of a perception it reduces their electric bill. For those folks it's all about the bottom line.
Few folks get residential PV because it pleases their sense of the aesthetic.
Residential PV is not, in and of itself, a remodel any more than a changeover in HVAC equipment.

[Mike 134]

If you're on the fence about solar and it's ROI, have you remodeled any perfectly functional rooms in your house? There your ROI is "it feels good/looks pretty, etc." I'm putting solar on my house and at 65 my ROI looks to be 8-9 years, but it will be pretty to look at and, in the meantime, and will more than halve my electric bill.

[bcroe]

I’ve been switching my oil usage to electric. My oil bill would have been at least $6k this year but now it will be zero. That’s because I’m using heat pumps now.

I think the extra cost of a few more panels is well worth it but of course like I said before nothing beats conserving energy .

I have been doing conservation for half a century, got the electric under 5000 KWh
a year. But more recently noticed, I used less nat gas every year, but my gas bill
kept increasing. The meter fee (had the same meter for decades) went from $2, to
$7, to $10 a month, they are determined to get my money no matter how much I
conserve.

Moving here, they said I could get connected to a new gas line with a MUCH HIGHER
monthly fee. That is when I went solar, 30,000 KWH a year and all the heat I want
in 2 buildings. DIY held the experimental costs down, but the way energy is going,
I may yet be in the black. Bruce Roe

[SunEagle]

The Prius is by far the worst car I’ve ever driven in almost every respect. Get the Porsche.

And that is why I won't get or can afford an EV. The Porsche is way too expensive.

I am still waiting on an EV truck but IMO that may not happen for the next few years or at least a couple of years after they shake out the bugs for new models.

[Cshama]

The Prius is by far the worst car I’ve ever driven in almost every respect. Get the Porsche.

[J.P.M.]

Unfortunately switching to EV's for us is not a great idea. We live out in the country and there are few charging stations or EV dealers for that matter. But I understand an EV might be the best for those that live in a place where they can charge it while at work or shopping.

If/When I ever get an EV, I'll be charging it at home and only at super off peak rates and times. From what I've seen of charging rates at stations around here (when I can find a rate), I'll be better off staying with an ICE considering cost per mile for fuel if I used a charging station.

An example: @ 30 MPG for an ICE vehicle and using a fuel cost of $4.50/gal. (the going rate @ Costco just now which is about the most competitive around), and say, 3 miles/kWh for EV "mileage", that's $0.15/mile fuel cost for the ICE.

With respect to fuel costs only, if the charging station rate is > ($0.15)*(3) = $0.45/kWh, I'll be better off staying with the ICE vehicle.

Once in a while I'll see a free charging station at a grocery store or such, but I'd not count on it.

What I'm also finding is that it's next to impossible to find a station with a published charging rate or a published rate schedule which seems to make it next to impossible to do any comparison shopping. When I do find a rate it seems always > that $0.45. I'm told Tesla charging may be quite a bit less expensive.

Your mileage and costs will most certainly vary.

And all this is before consideration for the 5 minute ICE fill up vs. whatever a charging time night be for the charging of an EV.

I suppose when an EV does appear in my future, I'll be doing a life cycle cost analysis for a level 2 charger in my garage vs. getting ripped off at a charging station.
However, at this time it seems the best per kWh rate I'll get from my POCO (San Diego Gas & Electric) is a super off peak rate of ~ $0.26/kWh which, @ 3 miles/kWh, makes for an EV fuel cost of ~ $0.26/kWh/3 = $0.0867/mile. Given the above costs I've assumed for the example, means I'd need an ICE that gets ($4.50/gal./($0.0867/mile) = 51.9 MPG or better. Given EV costs at this time, looks like a Prius hybrid might fill the bill for a lot less than most any EV even before considerations for the cost of a level 2 charger.

All that written, I also realize that vehicle ownership or "leaseship" is about a whole lot more than fuel costs alone. FWIW, I've still got my eye/mind on a Porsche Taycan and screw the Prius. So much for economics, but I stlll don't see the logic of an EV without off peak charging at home, particularly when coupled to a cost effective residential PV array and a super off peak T.O.U. or other cheap rate. Charging stations just don't seem the way to go from where I'm seeing the game.

[Cshama]

I’ve been switching my oil usage to electric. My oil bill would have been at least $6k this year but now it will be zero. That’s because I’m using heat pumps now.

I think the extra cost of a few more panels is well worth it but of course like I said before nothing beats conserving energy .

[SunEagle]

I agree the first step is reducing your energy consumption wherever possible.
That said, one's energy consumptions spans across many different types, electricity being one of them, others being things like natural gas or gasoline.

There is no way to get "free" gas or gasoline, but if you consider adding solar is a way to get "free" or incredibly cheap electricity in the long run, then it makes sense to consider switching some of the other energy consumption to electricity. And so, while you may be reducing your overall consumption of energy, you may actually increase your consumption of electricity.

EVs are the obvious candidate here. If a family with 2 cars ultimately plans to switch them to EV, that will significantly increase their electricity consumption, while actually reducing they consumption of energy. Switching gas heating to electric heating would be another example.

But for these cases, it can make total sense to oversize a system in prevision of these energy conversion.

Unfortunately switching to EV's for us is not a great idea. We live out in the country and there are few charging stations or EV dealers for that matter. But I understand an EV might be the best for those that live in a place where they can charge it while at work or shopping.

[scrambler]

I agree the first step is reducing your energy consumption wherever possible.
That said, one's energy consumptions spans across many different types, electricity being one of them, others being things like natural gas or gasoline.

There is no way to get "free" gas or gasoline, but if you consider adding solar is a way to get "free" or incredibly cheap electricity in the long run, then it makes sense to consider switching some of the other energy consumption to electricity. And so, while you may be reducing your overall consumption of energy, you may actually increase your consumption of electricity.

EVs are the obvious candidate here. If a family with 2 cars ultimately plans to switch them to EV, that will significantly increase their electricity consumption, while actually reducing they consumption of energy. Switching gas heating to electric heating would be another example.

But for these cases, it can make total sense to oversize a system in prevision of these energy conversion.

[J.P.M.]

I have to disagree with that. Oversizing in the beginning for things like electric cars, heat pumps etc makes sense because adding panels later is much more expensive.

If one goal of getting PV is to reduce an electric bill in the most long-term cost-effective way(s), the place to start is by reducing usage. Period. You will never pay less for power than the power you don't use in the first place. Besides, doing conservation first will have an added bonus of reducing the PV size - and so its cost.

And, if PV can be made cost effective for an application, the quickest way to kill that cost effectiveness is by oversizing.

In any case, determining usage as well as what that usage costs is a necessary and usually first step in the go/no go PV decision process.

The second step is to reduce that usage as best fits your lifestyle and goals keeping in mind that everything has a price.

Again, if the goal is a reduced electric bill in the most cost-effective way, what's usually considered the smart approach is to do the most cost-effective stuff first (like turning lights off, changing thermostat settings and things that don't require equipment changes). Usually, and in spite of what solar equipment peddlers will hammer and rant about, when conservation measures are listed by most to least cost effective, PV is usually near the bottom right down with new windows, meaning that PV is usually about the last thing done - if at all.

More often than not, if conservation measures are done in that way, it also often happens the conservation measures are so effective at reducing an electric load that adding PV becomes non cost effective.

I had a solar guru tell me a dirty little secret back in 1977 that the biggest impediment and the most effective competition to solar energy wasn't big oil or the utilities - it was conservation. Over the last years I've found that to be as true as anything else I may know about solar energy.

[mjs020294]

I have to disagree with that. Oversizing in the beginning for things like electric cars, heat pumps etc makes sense because adding panels later is much more expensive.

It depends how far into the future you are adding things like EVs. The sensible approach is reduce your output; do everything you can to reduce consumption because its generally much cheaper than adding solar capacity. Most electric companies have pricing bands so adding solar to get you well into the bottom band is also a very cost effective exercise.

If you're 100% confident you're will be consuming more in the next 2-3 years it could be cost effective to oversize. Solar prices tend to decrease and efficiency will increase so adding a second system later is also an option.

[SunEagle]

I have to disagree with that. Oversizing in the beginning for things like electric cars, heat pumps etc makes sense because adding panels later is much more expensive.

Still conservation has proven to be the cheapest way to reduce the electric bill. Having a large pv system then is needed makes it hard to justify an ROI unless money is no question.

[Cshama]

I have to disagree with that. Oversizing in the beginning for things like electric cars, heat pumps etc makes sense because adding panels later is much more expensive.