diy solar

diy solar

Will just posted an excellent video, check it out.

How much KWh would one need from your wonderful system to blow away the clouds that I have 300 days a year, Will?

Doing ROI calculations without the climate data is just silly, you mentioned several time the different local electricity cost, but not a single time the average weather conditions not mentioning a single time other constraints like shadows.
Worse, you pointed out the KWh one would get "every single day". Really?
Sorry, Mr Prowse, I won't follow you in that commercial!

And all these panels get mounted without any frames and any basement? (that easily cost more than the panels they carry)...

Readers, please have a look at my signature:
You get realistic models to evaluate your off-grid system including calculating the average SOC of the battery, the -tremendous- value of wasted energy during summer time and the number of days you will stay freezing with no juice out the sockets in winter with an empty battery.
 
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Doing ROI calculations without the climate data is just silly, you mentioned several time the different local electricity cost, but not a single time the average weather conditions not mentioning a single time other constraints like shadows.

I agree with the first part. But in fairness, he did say his calculations assume 5.5 hours of sun a day. One think he did not address is maintenance costs. Nothing lasts forever and once out of warranty, things like a failed inverter or charge controller can be drastically change that ROI. ,
 
I agree with the first part. But in fairness, he did say his calculations assume 5.5 hours of sun a day. One think he did not address is maintenance costs. Nothing lasts forever and once out of warranty, things like a failed inverter or charge controller can be drastically change that ROI. ,
Even If you live in a blessed region where you can count on a average of 5.5 hours on sun a day, that will not mean that you get 5,5 times the tag power value every day and -being off grid- that you even can use it.
Once the batteries are full, if you get more than you are consuming, you just waste potential energy.
 
First of all, that video was a direct response to his previous one, and is deliberately for his set-up, not a general calculation applicable to everyone.

Clouded days aren't necessarily a problem, diffuse lighting also generates power. You will need more panels, but that's not a deal breaker. I have 10kW of solar panels - at 63 degrees north here in Finland, which I think everyone understands are pretty extreme conditions for solar in winter. The difficult months for me are November, December and January. Otherwise, more power than I need.

My next car will be electric, so all that energy I'm not capturing right now would be used to drive that. I'm also using this power now already to process wood (cutting/splitting with electric tools) in summer/autumn when I have this excess power - essentially storing this energy for winter. I'll also double the battery, and that should get me through November as well, so that leaves only 2 months I would need to run the generator once a week/two weeks or so to charge the batteries.

I built my own ground mounts for these panels:

You can see the cost break-down in that post. Again, not saying this is applicable for everyone, but it is possible.
 
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I agree with the first part. But in fairness, he did say his calculations assume 5.5 hours of sun a day. One think he did not address is maintenance costs. Nothing lasts forever and once out of warranty, things like a failed inverter or charge controller can be drastically change that ROI. ,
The potential productive capacity of a PV system has no bearing on the calculation of a system's actual ROI.

All that matters for actual ROI is the difference in total earnings and savings between the two scenarios of making the investment in a solar PV system and not making the investment.

Which means all you should include in the Return part of an ROI assessment is the value of the energy actually produced and consumed, which has two basic values:
i. the savings value of the grid imports replaced, and
ii. the earnings value of selling the energy to the grid.

In an off-grid scenario the latter is zero, so the ROI is simply the cost of the alternative energy supply you have replaced, i.e. what would have it cost had that energy been purchased from the grid. One should, in fairness, use the cheapest grid supply option in their location for comparison.

The fact a system is capable of producing more than is actually consumed isn't relevant. Unused capacity has no value.

At least some grid-tied systems can get some return for excess capacity sold to the grid. But such a system may cost more as well (in order to meet regulatory approval standards).

Things like earnings from crypto mining have zero bearing on solar PV ROI calculations because you can mine equally well with grid power. The only financial difference between those two scenarios is the cost of the electrical energy used.

As to having power available when the grid is down, that definitely has value. But equally, the grid has value as a backup for when your own solar PV system is down. Outages can happen with the grid supply and with your own supply. Which backup option is then considered more valuable?

And power backup can be provided via other options, e.g. a petrol powered generator, which despite the downsides is still in many cases (but not all) a very effective and low cost way to have emergency power in an outage. Why spend several thousand $ on a solar PV / battery backup when a $500 generator and $20 of fuel can do the same job in many (but not all) instances?

Of course the capex considerations also come into play, e.g. a rural property where to get grid supply it might mean a $100k cost for the poles and wires connection by the local energy distribution company, vs building your own system. That's a different kind of assessment and one where much longer term considerations need to be factored in such as who is responsible for the cost of maintenance, upkeep and replacement of the power supply infrastructure, as well as the land improvement value of having grid access vs not.
 
Interesting how he Just Tickled the EV Charging as part of ROI.
Extract the cost of Petro you burn weekly/monthly and add that on top of the Payback and the ROI drops really fast !
Then figure that in Nevada 1 US Gallon (3,78L) of regular gas = $4.00 USD
The EV Availability in the USA is minimal compared to the rest of the Globe, my goodness, even in Africa you have more brands//models & choices BUT they are not held hostage by a Few Companies & their Lobbyists, who continue to hold it back. IF only the General Public knew what they are missing out on... (Don't start an argument, even Warren Buffets BYD is selling Cars/Busses & Trucks everywhere BUT North America which only see "some busses & trucks" from them.)
NationCityPrice in USD Regular/Gallon
NetherlandsAmsterdam$6.48
NorwayOslo$6.27
Italy
Milan$5.96

ROI also REALLY Changes if you Have an EV with V2H (Vehicle to Home) Capability as you then leverage the EV Battery as well and NO EV to HOME won't kill the EV Battery as they are for High Output use and a Home never has that level of demand, generally it would be less than 5% of EV delivery Capacity (real EV, not a piddly little hybrid). Remember EV Packs tend to be 350VDC+ and can deliver 1kA +, so a 10A+50A draw won't even cause it to blink power demand wise. (they are not ESS - LFP Cells).

ALSO FIT (Feed In Tariff) programs VARY A LOT and some really payback little when you look at fees, taxes and surcharges (yeah in some places it is nutz). There are places that pay back 50% only... so you sell at 5 Cents to Big Power but to buy back it is 10 Cents and they plop delivery fees and taxes on it... some in BOTH DIRECTIONS too no less ! IT ALL DEPENDS WHERE YOU ARE and WHo's Screwy System you are connected to.
 
Things like earnings from crypto mining have zero bearing on solar PV ROI calculations because you can mine equally well with grid power. The only financial difference between those two scenarios is the cost of the electrical energy used.
Sure it does. Do it with grid and it costs you money to make money. Do it with solar and it's "free" money to make money. The ROI is greater and happens more quickly, not to mention the crypto investment ROI itself.

So while I agree you can't include crypto in an analysis for the general solar user, if crypto mining is one of your planned uses, it can and absolutely should be included in the calcultions.
 
sure.
The calculation is not the same if the initial question is
-Should I drop my existing contract and live off-grid in my town condo
or
-How can I get my planned cabin located 30Km away from the nearest remnant of civilization.
No question that in the second case solar will be the clear winner.
;-)

Anyhow when considering off-grid solar, the usual way is not to begin evaluating the cost of electronics, but first look where you can limit your nightly consummation. Than to calculate how much battery you need to provide that energy for, -say- at least 48h without any inbound energy.
last to evaluate how you can recharge your battery on a sequence of cloudy days, while still diverting what your household needs to go on running

That will define how much panels you need and the corresponding electronics.
How much you will throw away in summer (>80%) is irrelevant.
 
ROI also REALLY Changes if you Have an EV with V2H (Vehicle to Home) Capability
Full ack!
The vehicles with that capability are however extremely rare. IMHO they should be made MANDATORY.

Sure it does. Do it with grid and it costs you money to make money. Do it with solar and it's "free" money to make money. The ROI is greater and happens more quickly, not to mention the crypto investment ROI itself.

So while I agree you can't include crypto in an analysis for the general solar user, if crypto mining is one of your planned uses, it can and absolutely should be included in the calcultions.
Crypto-mining is not worth any more on the very cheapest power providers and the Chinese are decommissioning their farms at a forced pace.
And you want to do it on solar?
 
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Crypto-mining is not worth any more on the very cheapest power providers and the Chinese are decommissioning their farms at a forced pace.
And you want to do it on solar?
You'll have to reread my post. No where did I say "I want to do it." Summarily I said, if it is being done, it can and should be included in ROI calculation. Not sure what the problem is with that statement.
 
My neighbors (most in their ‘70s) seem to have a different ROI calculator and factors that they use to rationalize their solar spending. Anything that makes Gaia happy has zero cost, so according to them their ROIs are all infinite. ;)
 
My neighbors (most in their ‘70s) seem to have a different ROI calculator and factors that they use to rationalize their solar spending. Anything that makes Gaia happy has zero cost, so according to them their ROIs are all infinite. ;)
A happy wife makes for a happy life and when you're 70, you want the few remaining days you have left to be happy... lol
 
Sure it does. Do it with grid and it costs you money to make money. Do it with solar and it's "free" money to make money. The ROI is greater and happens more quickly, not to mention the crypto investment ROI itself.

So while I agree you can't include crypto in an analysis for the general solar user, if crypto mining is one of your planned uses, it can and absolutely should be included in the calcultions.
Solar PV is not free, there is a capital investment to be made in order to generate that energy. An alternative use of that capex is simply buying energy in another way.

Bitcoin production doesn't care where the electrons used to make it come from. You can only include bitcoin output in the assessment of solar PV ROI if it were not possible to mine bitcoin with grid energy.

So the only consideration is the energy cost differential per bitcoin mined.

Consider that in some places you can go onto a wholesale energy pricing plan and time your use of energy at very low cost times of day, indeed the price of wholesale energy can and does go negative in Australia, especially in places like South Australia where there are often gluts of renewable energy supply in the grid (yep you get a credit for consuming energy from the grid). Obviously it's not negative price all the time but just like solar PV you can have storage to extend the time such low cost energy supply can be used.

One scenario (solar PV) has higher up front capex, lower operational costs (usually), the other (grid) has low capex, higher operational costs (usually). These are the only considerations which matter when assessing the ROI for solar PV.

What the electrons are used for doesn't come into it unless what you are doing is not also possible with grid power.

Interesting how he Just Tickled the EV Charging as part of ROI.
Yeah that made little sense.

Comparing the cost of running an ICE vehicle with using solar PV to charge your EV would only be relevant consideration if you could not charge an EV with grid power. IOW the value difference solar PV brings is the marginal improvement over using grid power, not the jump from using petroleum to electrons.
 
How much KWh would one need from your wonderful system to blow away the clouds that I have 300 days a year, Will?

Doing ROI calculations without the climate data is just silly, you mentioned several time the different local electricity cost, but not a single time the average weather conditions not mentioning a single time other constraints like shadows.
Worse, you pointed out the KWh one would get "every single day". Really?
Sorry, Mr Prowse, I won't follow you in that commercial!

And all these panels get mounted without any frames and any basement? (that easily cost more than the panels they carry)...

Readers, please have a look at my signature:
You get realistic models to evaluate your off-grid system including calculating the average SOC of the battery, the -tremendous- value of wasted energy during summer time and the number of days you will stay freezing with no juice out the sockets in winter with an empty battery.
Each point you bring up was addressed in the video… please don’t disrespect the host of this wonderful site.
 
Any income that is produced by or as a direct result of the PV is in scope. I absolutely would include mined bitcoin and its return as ROI.

You would do the same with grid. Your energy investment is by the watthr instead of upfront on solar. so in this case, you would track and accumulate your investment in grid power over time vs the return on bitcoin in that same amount of time.
 
Any income that is produced by or as a direct result of the PV is in scope. I absolutely would include mined bitcoin and its return as ROI.
You can claim ROI on mining bitcoin but you can't assign that ROI to the off-grid solar PV.

Say my neighbour and I each have identical bitcoin mining rigs. I decide to put in solar PV/battery system to power mine off grid while my neighbour leaves theirs powered by the grid.

The only ROI differential is the cost of the energy supply, because the output of each rig will be the same (on average over time).
 
Any income that is produced by or as a direct result of the PV is in scope. I absolutely would include mined bitcoin and its return as ROI.

You would do the same with grid. Your energy investment is by the watthr instead of upfront on solar. so in this case, you would track and accumulate your investment in grid power over time vs the return on bitcoin in that same amount of time.
Idk… if I run a business and sell widgets, lest say I make 10K a week… that makes the ROI on PV a few weeks…
Certainly, Bitcoin will produce funds from the used power, but I wouldn’t consider it part of the ROI, especially since it also raises the power consumption…

I guess, if you ARE Bitcoin mining, and you have a set power bill, the additional PV ROI could be calculated that way, but NOT the Bitcoin profit itself…
 
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