Solar questions

[mrchrisjordan]

Hello, my parents are interested in having solder panels put, and we met early this morning to discuss it. Through TEP, we spend around $200 per month on average, and we may be able to secure a set solar cost of $150 per month for the next 20 or 25 years. It appears to be a decent value. The fact that the house faces true south is a plus. TEP is increasing rates by around 7% each year, according to the man, so our $200 monthly average will only rise over time, while the solar monthly charge will remain at $150. The $150 each month will replace our TEP payment and go entirely toward paying down the solar panels' principle (about $40k). There's also a tax reduction of 26%, which seems like a fantastic deal!
The proposals will be delivered to us next week so we may review them.

I'm simply curious about everyone's opinions on this, especially if you've worked with solar before!

Thank you to everyone.

 

[wattmatters]

$40k for a solar PV system? Seems expensive. How big is it? Where are you located?

Where I am that would get you 20kW of grid tied solar PV plus circa 20kWh of grid tied lithium battery storage.

TEP is increasing rates by around 7% each year, according to the man

No idea what TEP is. Who is "the man"?

If it's the solar salesman be very wary about predictions on power prices beyond a few years out. The supply technology mix is changing rapidly in grids around the world and no one really knows how that will impact on supply costs.

My word of caution with such deals is they are not really selling you solar PV, rather they are really selling you finance, often quite expensive finance.

 

[HRTKD]

Should I get around to putting solar on my house, it will be a system with no strings attached. I'll pay cash or find my own financing. As wattmatters said above, 40k is a lot of money. The panels for a 20kW system should cost only $10k

 

[schmism]

The panels for a 20kW system should cost only $10k

The inverter(s) are another 10K, the racking is another 10K and then include permits, labor etc its right inline with what my friends have paid for turn key whole house systems that they have had installed.

the only thing I caution against is the kind of system that they spec. Most of these are grid tie only, no battery. This mean when the grid goes down and you have 20KW of power sitting on your roof your SOL. So those rolling blackouts in CA, or TX or NY.... your not immune to those same issues despite having shelled out $40K for solar.

I made this clear to a buddy that had a system put in. He asked several times thoughout the process, does this work with a battery and when the grid goes down. They basicly lied to him said yes. Well his solar edge system does NOT infact have the edgestore propritary battery and because of that will NOT work when the grid goes down. It has offset his entire electric bill so he is saving $200-$300 a month

 

[Hedges]

Anything someone tries to sell you is a good deal for them, not for you.
I think what these solar installs are mostly about is pollution credits which the company sells to smokestack industries.

California has mandated rooftop solar for all new homes. But, they allow as an alternative having a community PV system. Installing PV on individual houses costs 2x or 3x as much as commercial scale PV. If it is possible to own a share of a larger PV system and get a credit offsetting your power bill, that would be better. All it takes is laws/rate schedules allowing such a credit (i.e. just an Act of Congress)

Because PV has come down so much in price, it can be a cost-effective alternative to buying from the utility company. Thing that matter include how much sun and shade you get, and utility rates. Here are the figures I use:

$1.00/watt purchases PV panels, inverters, rack mounts, electrical stuff. Over 10 years, figure $0.05/kWh. Possible repairs and over 20 years $0.03/kWh
My labor is free, but if system is installed by a company that could add another $1.00 or $2.00/watt. Now over 10 years $0.10 to $0.15/kWh

Your $40k estimate should be for 13kW to 20kW of PV. That would supply a large house. Maybe they are offering a smaller system at higher markup and profit for them.

Compare to utility rates in my area:
$0.15 off peak, $0.50 peak times

Other parts of the US:
$0.05/kWh

For me using my own labor, a clear win if I expect to remain in the same place.

Want backup during power failure, or off-grid? That takes batteries. It is worth extra to keep the lights on, but beyond a single light bulb and your internet/phone, batteries need to be big. They are expensive.

$0.50/kWh for batteries, over their lifespan of 3 to 10 years.
(some home-built DIY batteries can be $0.05, but not everyone can handle the work and safety issues.)

Generator burning gas, diesel etc:
$0.50/kWh

 

[wattmatters]

The inverter(s) are another 10K, the racking is another 10K and then include permits, labor etc its right inline with what my friends have paid for turn key whole house systems that they have had installed.

Your $40k estimate should be for 13kW to 20kW of PV.

Man, grid tied solar PV seem so expensive to install in the US.

A 13kW grid tied solar PV system in Australia will typically cost ~US$8,000 fully installed by solar PV professionals, a bit more if using premium kit and/or you have a complex/difficult roof, and less if using value for money kit and/or a simple roof for installing.

Here the benchmark typical price is ~US$0.75/W for a complete solar PV system fully installed by good quality solar PV professionals.

Solar / grid tied batteries (commercial type, not DIY) are ~US$0.75-1.00/Wh fully installed by solar/battery professionals. This would include operating with the solar PV in isolation from the grid when required during grid outages.

Solar PV is almost always a great investment for Australian homes with payback periods of 4-5 years being normal. Batteries however suck financially with payback periods measured in decades. You add a battery here for reasons other than saving money, usually for outage protection.

 

[OffGridInTheCity]

I have a larger off-grid system that generates 18,000kwh/year. This is panels, charge controllers, battery bank, Batrium, inverters, ATSs, UPSs - the whole shebang involved with off-grid. 2/3 of this I did myself for significant $ savings - particularly around the battery bank and a ground mount array.

I've kept meticulous records and the price tag to date is (about) $1.60/kwh - to enable me to generate 18,000kwh/year independent of the grid.

In my case, I wanted a chance for my 18650 battery bank to last 10-15-20yrs so I made it much bigger than needed and achieved a 40% average DOD - but this raised this the price to $2.30/kwh.