Handy Bob Solar

[DreamWeaverBus]

Hey yall!
I'm about to start my electrical budget, which I THINK means I first need to figure out how many watts I expect I'll use. Then figure out how many solar panels I'll need and batteries, and the other equipment like battery monitors and charge controllers.

Now, I recently found Handy Bob Solar's RV Battery Charging Puzzle:
https://handybobsolar.wordpress.com/...ging-puzzle-2/

I read the whole thing. Took like 5 hours. I am not an electrician. I am new to all of this. But I intend to learn so I know every bolt and wire in my Skoolie. When I found this Puzzle I was honestly relieved, because I had been highballing it and he seemed to relieve some of that mania. I've seen people share his Puzzle here and there, so I'm getting the impression he's legit and not blowing hot air.

So I wanna ask: yall think his advice is legit? Good advice? Good methods? Can I rely on what I learn there?

He mentioned that the wattage or amp hours of many appliances are set as so they don't EXCEED said amount, not the amount they actually pull. So as long as I stay within the max pull on my allowance, I should be good, right? Also assuming I use thick wires, keep the controller close to the batteries and panels, ect. Am I understanding things correctly?

I feel like my current issue is that I'm studying and doing my homework, but I have no one to check my homework lol So I come to the forum!!

I can see myself in my bus already... it's a ways off but all I gotta do is sell my car and I'll have the money... I'm excited and undaunted.

[Iceni John]

Handy Bob has some good points, but for a more reasoned approach to planning a PV system the good folk at the Northern Arizona Wind & Sun forum have experience and wisdom sufficient to answer any questions you will ever have. It's well worth spending some time reading the various sections there. If some of the experts there say to do or not do something, heed their advice!

John

[DreamWeaverBus]

Thanks!! I'll check that forum out!!

[JDOnTheGo]

Yes, Handy Bob is legit.

Nothing replaces some actual measurements. Of course, that is impossible until you have the various equipment in action. So, the best you can do to start is use the listed power consumption. You will likely find that the actual draw over time is less than listed. A water pump is a good example. They typically draw a good bit of power (5-6 amps) but they are in operation a very small amount of time - maybe 15 minutes a day. So, total impact on your energy budget is low.

Just for example - since you are in learning mode. That pump pulling 6 amps @ 12.5V is pulling 75 watts. If it does that for 15 minutes, that is about 19 Wh (watt-hours) or 1.5 Ah (amp-hours) @ 12.5V.

[miltruckman]

I am just wrapping up my electrical. And i found there are so many extra incidental parts you will need that you should plan at least 25% extra in the budget to cover them. Things like wire, terminal blocks, buss bars, terminals, lugs, fuses and breakers, clamps and wire ties. They all add up.

Bill

[DreamWeaverBus]

JDOnTheGo
I had a feeling he was, thanks for your input! I also had a feeling I wouldn't be able to measure until I had the equipment, which means I already spent the money at that point... Handy Bob himself says he has 345 watts of panels and 450 amp hours of storage, and he can apparently run power tools and his wife can run the tv and a sewing machine at the same time.. that's pretty dang good! It makes me think I can probably do something pretty similar and get what I need.

I'll be wanting to run:
small fridge/chest freezer
water pump
water heater (on demand)
tv & video games (on occasion, not every day)
laptop
internet goodies like router, modem, wifi hotspot, signal booster (I want to be a writer and/or youtuber)
lights at night, and then low lights, I do good in the semi-dark
cooking:
coffee pot every day for coffee and tea
(I could make sun tea and get a press though)
portable induction cooktop
rice cooker & steamer
portable induction oven (occasionally)
mini toaster oven, mb an actual toaster
mini deep fryer (occasionally)

I'm sure I'm missing some things but cooking and internet would be an often, everyday thing. Also hot water but I can reduce my shower time and habits. Without running actual numbers it seems like I should be able to do pretty good like Handy Bob. Especially if I got more watts. I was THINKING about setting myself up with 600 watts worth of panels. Or starting with 300-400 and adding panels and batteries as I can afford them.

I'm getting used to the watts/amp hours/volts talk, but I also have a couple friends who are electricians, I already asked one of the if he could be available to check my math and my work, and he's down, so that's good. Someone REALLY should check my math so I don't blow up my bus or get hot skin or something terrible!

If I'm taking a shower or cooking and therefore using the water pump, well, you can only do so many things at once right? hopefully I wouldn't over draw on the power. In my gramma's house we can't run the deep fryer and the air conditioner at the same time without flipping a breaker switch.. lol Good thing I'm already used to the idea!

milktruckman, thanks for that, I figured I would need extra room for stuff like wiring and such. 25% extra isn't too bad, but it adds up I'm sure. Something to keep in mind.

[JDOnTheGo]

If interested in seeing another energy budget, provided totally from solar, mine for my last coach is listed here:
Dutch Star Energy Audit - JdFinley.com

I haven't published the data from my current coach yet as I am still nailing down some numbers. However; it is an all electric coach with 10 kWh lithium battery bank and 1740 watts of solar.

[Jolly Roger]

I ain't an electrician so when I am in my design/engineer/budget type mode I like a book called
Managing 12 volts.
How to upgrade,operate,and troubleshoot 12v electrical systems.
Written by Harold Barre.
It covers RV's,boats and sailboat systems.
Gennies with inverter/converter,solar,wind.
It has a formula/calculation for battery bank design in amp hours and a lot of good info for some one trying to wrap there head around there ideas,wants,needs.
Has helped me decide what needs to be 12v or 120v?
But I guarantee your needs and wants are different than mine to a point.
But the book I mentioned does have several pages to read for figuring power requirements/batteries for your requirements.
Good luck.

[DreamWeaverBus]

Thanks JD, I'll save that to my big lists! Looks pretty good! The 650 watts of solar sounds pretty similar to what I'd like to have.

And thanks Jolly Roger, I've seen that book on Amazon too, saved to my wishlist. I ended up getting "Build Your Own Low-Budget Solar Power System" by Steven Gregerson. I think it has an energy budget chapter, haven't finished reading yet.