The calculations used in my solar project were very conservative. Perhaps you are dealing with the wrong people.
Charging a Tesla with a completely off grid solar/battery/inverter system
- Thread starter Cujet
- Start date
I was thinking the amount of ramp up due to his own off grid solar. If you look at his backyard off grid solar, it is replacing some potential demand he would put on the grid (which is how it make sense financially), and the grid tied solar would have bump some demand off some natural gas / coal / nuke supply off during the day time. This means when he is switching from solar to grid (i.e. use a different set of AC) he would be contributing to the grid's non solar ramp up, which the gas plant would likely need to ramp up earlier and waste some energy to provide for, which leads to waste vs if he was on the grid using non solar to begin with. Unless he has enough battery storage to go pass the duck curve ramp up time (i.e. between 5pm to 9pm) then it would happen, and if he his battery to sustain pass 9pm or so then it would be pretty expensive vs using the grid if the grid is not too expensive at that hour.
My thinking of offsetting peak time load is to shift some thermal use cases around, like precooling the house, solar freezer then use ice to cool the house during peak evening time, electric dryer, electric / hybrid water heater (and take shower during day time peak hours). It is not sexy and it is quite 3rd world on the convenience scale, but it can be done without grid tie. Or, you move plug around between different time of the day, which is also quite 3rd world on convenience scale.
One thing about his backyard solar: despite losing his yard area to a pile of on the ground solar panels, he can move them to another house if he moves.
It really depends on the people and the location. I have seen numbers from guys that told me right away it doesn't make sense, then I have people who told me it is a no brainer because it breaks even and it saves the world, assuming no risk in terms of future tech advances or future energy price not growing as fast, or gov policy change so net-metering got axed or something like that.
In my case I am usually tier 1 fixed price (26c/kwh), with summer time going into middle of tier 2 (32c/kwh), no EV, north facing roof, our local already has "clean energy" plan that is cheaper than PG&E's regular plan, it is a no brainer to use the grid as roof top solar would be twice as expensive. However if I am in another area that needs AC 247 and have a big south facing roof on a 1/F house I am building for myself or need a new roof right now, then it makes total sense to do roof top solar with net metering.
JHZR2
Staff member
Batteries have finite calendar life, so there is BS in the lifetime claims.
Now we need double the battery to charge the car. Which means double the copper, aluminum, and lithium, even if we avoid Ni and Co in the charging pack.
The upside is you become your own local gas station. There are worse things to be.
Now we need double the battery to charge the car. Which means double the copper, aluminum, and lithium, even if we avoid Ni and Co in the charging pack.
The upside is you become your own local gas station. There are worse things to be.
I looked at my PG&E bill today, on the electrical part only. We locally have Silicon Valley Clean Energy as our "generation" and then PG&E as our distribution / grid, basically SVCE will buy generation capacity at 50% renewable for everyone and then guarantee to be slightly cheaper than PG&E's own generation portfolio, so in theory everyone wins.
I see that PG&E is making $106 on the grid (distribution is about 50% of that, others being PCIA, transmission, conservation incentive, wildfire fund, public purpose program like LED bulbs and rebates for appliances, etc) and the generation is only $32, that's like only 1/4 of the total cost.
So let's say you can somehow go off grid with your own battery storage and you lose 50% of the capacity without the grid, into batteries, inverters, DCDC converters, overbuild capacity you are not using, etc. You may still come out ahead if you know what you are doing. Efficiency is probably the last of your concern if you can get your panel cheap and you have good installation cost, in the right location.
Any of you folks watch the banned movie "planet of the humans" by Jeff Gibbs, and Michael Moore?
Essentially the movie suggests it requires more oil to produce the solar panels, batteries and all the gear required to run them, then the oil they will save..
Essentially the movie suggests it requires more oil to produce the solar panels, batteries and all the gear required to run them, then the oil they will save..
Not heard of it, but I had a professor (the one I study from, not someone off internet) told me back in around 2008 or so, that solar panel back then would requires about 20 years of energy to be manufactured and then after that it would be free energy till they are damaged. Energy, not oil.
Today's solar panels are more efficient to make and produce more electricity than before, so that number can not be right. If you consider all the human labor required as well then obviously the path to anything industrial would require a lot of energy to make human labor comfortable, and will be a net negative. I would imagine nothing would be net positive with human involved.
Also don't forget everyone pays different price for oil and electricity, nothing is free in energy and locations matter.
If you drive through the Central Valley and see new home tracts, they all have solar. The incremental cost to install solar in a tract home vs a single installation (like mine) has to be half. Everything is built by design in an assembly line fashion.
If I was paying close to 30 cents a kWh, I think solar would be worth it.. But not at Iowa's 12 cents.
And isnt the energy used to produce solar panels and gear produced using oil and gas mainly? Ive never heard that solar panels and gear could be produced by 100% renewable energy sources.
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Spoiler alert: Will change the subject.
I have nothing against EV vehicles and SOMEDAY one might be in my future, although somewhat impractical at the moment. But living on 20 acres, with no close neighbors, in a state where the wind is always blowing (at night too, where solar falls flat), any charging of my EV would come from the wind. My EV would get the “free” recharges from wind and I suspect the charging system would be much simpler.
I have nothing against EV vehicles and SOMEDAY one might be in my future, although somewhat impractical at the moment. But living on 20 acres, with no close neighbors, in a state where the wind is always blowing (at night too, where solar falls flat), any charging of my EV would come from the wind. My EV would get the “free” recharges from wind and I suspect the charging system would be much simpler.
40 mpg. $3/gal. 7.518 cents per mile.
In reality, an Accord Hybrid or Camry Hybrid does better than 40MPG (most seem to hover around 44mpg) on average, and gas at Costco locally is $2.86
To the first point, I always suggest EV owners use a dedicated meter to measure the energy purchased. The few that do are amazed at just how much it actually costs. The nonsense dashboard readout of "watt hours per mile" is just that, utter nonsense and is not directly correlated with power purchased.
About the 12 cents per KWH thing..... In many locations, the electric rate may be at or near 12 cents per KWH, but the taxes, fees, charges, connectivity assessments, and general "bill bloat" conspire to drive the costs way the hell up. Here in Jupiter, FL, I pay FPL a rate just under 12c. But the total invoice comes to nearly 22 cents per KWH, depending on consumption, and if over 750KWH per month, I pay a much higher "penalty" rate.
If we take the dashboard watt hours per mile (say it's 300) and multiply that by our 12 cents per KWH, we get a truly fantastic number. So fantastic, it begs a second much more accurate look. AND, if that's not right, then maybe the natural gas/coal/oil/water or atoms consumed per mile "ain't" right either.
The total solar irradiance/insolation in TN is lower, which means more panels would be required. Annualized solar output in East TN is about 4 hours per day. Here in Jupiter Farms it's 4.7. That's a significant difference requiring 20% more panels in TN.
If the claim is that TN has many weeks of no sun, that's true at times too. And, that's where such systems may fall very short.
Got it. I was curious if you were including maintenance costs as well. Numbers without context are hard to interpret. And I value your knowledge.
Why would you get solar in Iowa when the sun is nowhere close to California sun?
Let's say China is making the solar panels, a few of their major producers probably make them near Shanghai, their grid gets their power in the typical coal 2/3 + hydro of 1/5. As I said previously they try their best to avoid importing gas and oil. (according to wikipedia).
SolarCraft Response to COVID-19 - SolarCraft
Browse our solar energy myths & facts online. SolarCraft offers dependable solar system installation services throughout California. (415) 382-7717
solarcraft.com
So if you believe in National Renewable Energy Lab, the ROI energy time is 4 years, not lifetime, not 20 years. I would imagine even with fudge factor it would probably be 8 years instead of 20, so it would be a long term benefit to have some solar to cover AC need.
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If he has an EV with HUGE battery, and work from home, then he probably doesn't NEED to charge a power bank then charge his EV. I am not sure if we have software that works in this kind of setup, to have the EV's charger increase and reduce the current so that it won't cause regulation or conversion problem. Someone needs to come up with a standard on this.
Good point, maintenance costs like brakes and oil/transmission/coolant service are non trivial and are not included in my admittedly simple "energy cost per mile" calculations.
OVERKILL
$100 Site Donor 2021
Why would you get solar in Iowa when the sun is nowhere close to California sun?
Let's say China is making the solar panels, a few of their major producers probably make them near Shanghai, their grid gets their power in the typical coal 2/3 + hydro of 1/5. As I said previously they try their best to avoid importing gas and oil. (according to wikipedia).
SolarCraft Response to COVID-19 - SolarCraft
Browse our solar energy myths & facts online. SolarCraft offers dependable solar system installation services throughout California. (415) 382-7717
So if you believe in National Renewable Energy Lab, the ROI energy time is 4 years, not lifetime, not 20 years. I would imagine even with fudge factor it would probably be 8 years instead of 20, so it would be a long term benefit to have some solar to cover AC need.
Yep, every step of the process is dominated from fossil fuels. From the mining, to the processing of both the silicon and steel, to the container ship burning bunker, to the tugs that usher it in, to the transport truck that brings it to the place it will be stored and sold from.
There are a significant number of steps in that process. I know we've talked about it before, but shipping is filthy. There's literally one green container ship on the planet, and the Russians own and operate it (Sevmorput).
I have a remote garage that is off-grid. The design of any off-grid PV system needs to be based on your loads, otherwise you will be dark on cloudy days and you'll shorten the lifespan of your battery bank with to much DoD(depth of discharge). My system is designed to provide 2.5Kwh of electricity a day, so it has a 10Kwh battery bank IOT allow for 2 consecutive days of zero solar gain and still not discharge my battery bank below 50%.
My system is fully inspected and permitted but I live in a county that allows the owner to pull any permit they want to pull. I did the installation myself 11 years ago.
Solar panels are dirt cheap now (the take-off 230-260W ones anyway), good charge controllers and inverters are not.
I'm not going to watch the video but a quick glance of the thumbnail tells me he isn't set up for anything but full summer sun.
My system is fully inspected and permitted but I live in a county that allows the owner to pull any permit they want to pull. I did the installation myself 11 years ago.
Solar panels are dirt cheap now (the take-off 230-260W ones anyway), good charge controllers and inverters are not.
I'm not going to watch the video but a quick glance of the thumbnail tells me he isn't set up for anything but full summer sun.
What am I missing here other than state taxes?
Youtube banned Planet of the Humans a while ago. Not sure why they changed their mind but seems like bigtech is starting to back off a bit. Im not agreeing with the movie, but it reminds me of the extremes of information we are presented lately. One side says one thing and the other says the opposite.
youtube.com/watch?v=Zk11vI-7czE&t=92s
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