Controlling 3.6kW of Solar EV Charging with an Arduino GIGA R1 WiFi
blog.arduino.cc
blog.arduino.cc
Few installations bother with tilting panels any more. 20 years ago, when solar panels were expensive, that was a thing. Not so much any more.
That you can get 13KW of new panels for US$6000 is amazing.
And even if you're losing a small amount due to an inefficient angle, just get more panels!
However, at grid scale a few percent difference in cost or output can have dramatic impact on profitability so there's a lot of seemingly trivial optimizations going on. Some instills go so far as to aim some non tracking panels slightly to the east or west because slightly more valuable kwh beats slightly more kwh.
People think renewables are efficient in some way. They aren't. It's literally the most wasteful way to produce power because it doesn't get here when we need it and grid scale storage is orders of magnitude more expensive than production.
Which is why so many grid scale solar installs come with enough batteries to store ~50% of daily output. It's not about nighttime power it's about reducing demand for peaker power plants. Basically combined cycle natural gas operates at ~64% efficiency assuming long term operation, but open cycle has much lower efficiency and thus much higher costs.
[[Citation needed]]
> grid scale storage is orders of magnitude more expensive than production.
[[Citation needed]]
PS: I have little interest in looking for citations when you can do your own research using 2024 data.
It can provide 400MW of power for 4 hours before it goes offline and cost $560m.
You need 6 of them to provide 24 hours back up. That's $560M * 6 = $3.4B. That's not counting the three times as large solar plant that you will need to build to charge the battery or that the battery will lose 50% of it's output within a decade unless you build an even larger battery installation to prevent full discharge. On top of that to prevent yearly black outs you'd need somewhere between 3 to 20 times the capacity above depending on region and climate.
Meanwhile the latest nuclear power plant produces the same power without degradation for less than half the rosiest estimate above and was build in a country with no history of nuclear power and no indigenous expertise: https://en.wikipedia.org/wiki/Barakah_nuclear_power_plant
Pairing batteries with solar provides actual useful power from solar for most of the day. You don't need both 24h of batteries AND redundant solar farms to get 24h of energy. Extremely redundant solar costs less per kWh. Therefore a combined system will cost less, provide more useful power, and charge the batteries at zero additional cost. I'll stick with batteries alone, but include that zero charge cost as part of a cheaper overall system.
Construction costs vary by country so you need a country with both battery systems and nuclear to get an apples to apples comparison. For the US "In 2023 costs had increased to $34 billion, with work still to be completed on Vogtle 4.", with work still to be completed on Vogtle 4, and that's just construction on two 1.1GW reactors. https://en.wikipedia.org/wiki/Vogtle_Electric_Generating_Pla...
400MW * 6 = 2.4 GW, 4h * 6 = 24h. 36 * 560m = 20 billion so well under that 34+B even before considering the cost savings from solar. We are comparing with Nuclear at 2.2GW which again goes offline for long periods, but we care about orders of magnitude so redundancy is a non issue.
Now you need to consider operating costs for both systems. In constant dollars without subsidies construction works out to roughly 1/3 of nuclear total lifetime costs ~1000 workers + fuel + insurance + new equipment + decommissioning adds up. I'll be conservative and double that 34 billion instead so 68B.
Actual studies look into foretasted costs. However for orders of magnitude 5%/year of install costs per year in maintenance would be equivalent to creating redundant facilities to cover 50% degradation in 10 years, so that's conservative as swapping out batteries would lower costs here. Lifetime costs should therefore be below 20B + 20B * 5% * 50 years = 70B ie roughly the same as Nuclear per kWh and far more flexible.
Now, you can easily quibble about these numbers but your not getting an orders of magnitude difference here.
Feel free to provide better numbers. Those are the two largest most recent projects. That those numbers disagree with what studies say they should be aren't a problem with the numbers, but problems with the studies.
Also you should read up on the difference between power and energy since you're confusing the two in pretty much every line of your post. Watts aren't joules and joules aren't watts.
I did provide a US example for an apples to apples comparison. Providing lower numbers is irrelevant when higher numbers already prove the point.
> Also you should read up on the difference between power and energy since you're confusing the two in pretty much every line of your post. Watts aren't joules and joules aren't watts.
Don't hand wave, pick a single example.
If you don't understand my notation you can simply compare 2 * 1.1 GW nuclear reactors * 24h = 52.8 GWh per day. The battery example you gave was 400MW * 4h = 1.6GWh per day. 52.8 GWh / 1.6 GWh= 33x. I used 36x for a total of 20.16 Billion dollars.
https://undecidedmf.com/have-we-been-doing-solar-wrong-all-a...
This guy did some interesting real-world testing in a bunch of different circumstances - https://www.youtube.com/watch?v=5AVO1IyfA9M
The other major advantage here is that you can use them with farming and actually do something with the space.
In addition areas where it snows sees a dramatic uptick in solar power because of the reflection of the snow and not needing to brush the panels off.
vertical panel layouts really open up a LOT of options that were not available before. (using them as fences, putting them on sun facing walls of homes spaced off and letting the pass through sunlight hit the other side). There's a lot of possibilities here).
So vertical makes a lot of sense on large scale solar farms I think, even more so when you consider the land can be better utilised.
On domestic scale, where you can easier shift your load to match your production AND you might already have a roof with the right front and pitch, normal pitched north/south facing installations might make more sense.
They end up covered in moss and mud.
I'd recommend doing it at night, because I got a nasty zap off mine when presumably some of the mopping water got into the electrics and came up the metal mop pole .. (the electrics are all supposedly fully waterproof, but I guess on my 10+ year old panels stuff has degraded)
If you're selling it back to the power company then this might not be a problem unless you also have resell limits.
However, the duck curve means many grid scale solar instillation still use East/West solar tracking to collect power when it's more valuable ie mornings and evenings. It's a great example where optimizing for profit results in an counterintuitive result.
But if there were any moving parts I couldn't imagine them still being operational after this time.
You can also get used panels for dirt cheap. I bought 5kW of used panels for $750 a few years ago.
If you're in Australia or something, sure $0.20/kW is a good price.
Ironically, the little bits of metal to hold them to the ground cost almost as much, and the inverter and batteries both cost more.
At signaturesolar.com you can buy made in USA panels for $0.37. If you go wholesale, I've seen them as low as $0.26.
Or us$ 360/kwh. And this is in open market. Government subsidized rates are even lower.
Farmers were given a solar water pump scheme with 90% subsidy last year.
10kwh solar panels + water pump for that capacity + installation + steel work for inr 90k or us $ 1092.
(I'm joking, the tariffs on solar panels in the US actually started with Obama...)
https://grist.org/climate-energy/obama-administration-slaps-...
I did look to try to find out if the tariffs can explain the full difference in cost, but I haven't found the latest tariff rates...
There may well be additional effects too.
Tilt systems aren't worth the money. They cost too much to make and with the same money more panels produces more power.
It's an apples to oranges comparison. Solar panels don't provide power overnight for example, but people place a lot of value in being able to use power at night. Likewise the grid scales up and down to meet the demands placed on it which a basic solar setup (i.e. without batteries) can't do. Then there's reliability, transmission etc.
They've spent an insane amount of money on solar panels - that's all out of that number, those are net profits.
What happens when they have 50% or maybe near that 100% of power coming from renewable power?? They've made a lot of money off of us while we also paid for the costs to attain the renewable system, once it's in place - why should they get my money anymore?
Why are people profiting off of a necessity to life anyways?
For that you need a properly sized off grid system, which can easily be 20-30 kW of solar and 50-150 kWh of batteries. Enough to get you through 50-10 cloudy days (depending on your location) with less than 1 kWh per day per kW from solar and 40-60 kWh per day of electricity use.
In the US, I think the "pinch point" for off-grid systems is usually in the winter for an all-electric home. Shorter days and more likely to have multiple fully cloudy days in a row, at least for a lot of the US.
Delivery charges, mostly -- it costs a lot of money to build and maintain a power grid. Wholesale prices in my state are around 4.5 cents/KWh, but delivered prices are much higher (around 33 cents/KWh depending on rate plan).
This is my thinking behind delaying getting some panels for my own home, if they're getting cheaper AND more efficient, surely that's going to have knock-on effects on the suppliers too?
Everything on Amazon looks like it was designed by the Chinese to start the next great Chicago fire.
Or is it better practice to use multiple 20a controllers?
Should the link point to the original source? https://www.hackster.io/racingtogreen/solar-powered-ev-charg...
They are also much cheaper than microinverters, safer, and more reliable.
Or you can use SolarEdge optimizers, they are simple and cheap (<$100 per module).
Both support automatic shutdown, so you can safely de-energize the entire system if needed. It's a problem for classic string inverters.
And most of the more powerful inverters require a grid connection because they can't work in an "islanded" mode.
But now I see products like MKR, Portenta, even proper industrial DIN-mounted controllers that look quite capable. Those in the know, what's the current landscape, what ecosystem is worth buying into?
IMO: No.
Arduino, as a company, wants that to change, but I have yet to see anyone take them seriously. Most of the "industrial" Arduino products are unsuitable for purpose; they lack critical features which would be required for those applications like protected inputs, wide range power input, or field bus interfaces.
Why would you use a Raspberry when an Arduino will do everything required? If you don't need a full Linux OS, then why waste it on something that just doesn't need it?
I think Arduino boards are best suited for what they were originally designed for: education. While that covers some of the hobbiest market, it doesn't cover all hobbiests.
Depending on all of the things you listed just sounds like lazy to me. /s
I actually meant the Pis are easier to program since development can be self-hosted. Uploading a program to a microcontroller after each build is a royal pain in the bottom. Debugging (with a debugger) is also annoying, both from the perspective of setting up the software and having the necessary hardware.
With respect to laziness, I hold two points of view. I definitely agree the inefficient of resources should be viewed in a negative way. This is especially true when a solution goes from bytes or kilobytes to megabytes or gigabytes. More critically, I believe that laziness is a negative when the inefficiencies lead to less robust code. On the other hand, one of the chief benefits of computers is to reduce the burden placed upon people. Setting up a toolchain for microcontrollers can be nearly as complex as developing code for the microcontroller itself. That strikes me as wrong.
Aside: I periodically write software for microcontrollers for fun. One of my favourite exercises involves prototyping with high level code, such as using Arduino libraries, and rewriting it using increasingly low level code. It is how I approach learning a microcontroller, but I am also extremely conscious of both volatile and non-volatile memory usage. I am definitely sympathetic with your notion of avoiding laziness.
On the other hand, we should also realize that microcontrollers are often used because we are "lazy". There are many cases where microcontrollers are used even when a basic circuit can accomplish the same task since it is cheaper to throw an absurd number of transistors at something than it is to pursue more efficient solutions. (Labour costs add to project costs, along with the number/type of components, board size, the relative ease of iterating code verses iterating on board revisions, etc..) There are reasons beyond the challenge of generating the most efficient solution possible to consider because the efficiency of development is also a factor. As someone who pursues software and hardware development as a hobby, I often bemoan the state of affairs of commercial products. Yet I also realize that commercial development, or even the motivations of other hobbiests, leads to different perspectives.
The advantage of the platform is speed of development, not engineering good practice or mass manufacturing.
It's a stand alone server with a simple Web UI and takes care of charging your car with solar (or grid, if there is not enough solar). IIRC it offers three modes: 1. charge solar only, 2. charge with at least 6A, boost if there is more solar, 3. charge independent of solar. You can also configure charging targets, e.g. stop at 80% SOC.
What's with the vaguely-FUD commentary about EVs?