House Battery and Energy Management

[rebelrider.mike]

Yeah, I've wondered about old gasoline and efficiency. I've never actually had trouble running engines on old gasoline. (As long as there's no water at the bottom of the tank.) But that's exactly why I want a dual fuel generator. The place I got my propane from was called All American Propane. They did the recertification and filled it up. The price was $2.50/gallon or $0.60/lb. About the same as everywhere else in my area.

I only have one good place to put the generator. Right under a window, which we're not supposed to do. I plan to install a CO detector on the inside next to the window. I'm also thinking of extending the exhaust pipe away from the house a bit, so the majority of the exhaust will not be nearby.

I've read that some propane generators use fuel fast enough that smaller bottles will get too cold to function properly. I haven't seen anyone complain about the Wen generator specifically, but I figure that's another good reason to have a larger tank. I also have a couple smaller tanks, so during a longer power outage I can heat water and cook things if needed with my gas grill and Colman stove. All outside of course.

I have about 2.5-5 gallons of ethanol free gasoline stored at home. I use it for anything with a carburetor. Mostly my mower and motorcycle, but I have a few other small engines that are carbureted too. I know people have lots of different opinions on ethanol free gasoline, but I find it's much better for carburetors since ethanol doesn't play well with aluminum. Fuel injected engines have mostly stainless steel fuel parts (I think) and the ethanol doesn't seem to bother them.

The heat pump stuff has me a bit excited. I kept building tables and crunching fake numbers late last night, and discovered that between the efficiency of the heat pump, installing a modest solar array, and selling small amounts of electricity to the grid, I could potentially reduce my electric bill by 83%. And that's with the house as it currently is. I still plan to add ventilation and insulation to the attic, replace the water heater with a heat pump one, and maybe replace the old freezer with an energy star compliant one. As well as other stuff. Just for fun, here's my solar chart with the heat pump added in:

I wonder how much money we'll save on cooling. Right now, during a heat wave, we could have 5 window A/C units running. Since A/Cs and heat pumps work basically the same, I don't know if the difference would be dramatic. On the other hand, with the heat pump, that's 5 windows that are closed instead of open to fit the A/C units. The units add up to about 25,000 BTU vs the 36,000 BTU of the heat pump. Also, all but one A/C unit run their fans all the time. The heat pump would shut its blower off when not in use. The fans don't use much power, but running 5 for 24 hours a day must add up.

 

[Korishan]

I only have one good place to put the generator. Right under a window, which we're not supposed to do. I plan to install a CO detector on the inside next to the window. I'm also thinking of extending the exhaust pipe away from the house a bit, so the majority of the exhaust will not be nearby.

Another good reason to go with propane.
And putting an extended muffler will help keep it quieter, too. So win-win there. I plan on doing this to my generator, too.

I've read that some propane generators use fuel fast enough that smaller bottles will get too cold to function properly.

Same, and makes sense. I've even had a small tank get frosty while using it with a Coleman heater. So it's definitely possible.

I know people have lots of different opinions on ethanol free gasoline

I would switch everything over if I could. And yeah, ethanol infused fuel causes issues with carbs. Mostly that gummy gucky stuff. not sure where that crap comes from. It's not fun tearing apart a carb to run the files/brushes thru it to clean it out so it runs like it's supposed to every year, sometimes more than once a year.

 

[OffGridInTheCity]

I have 10 x 100lb tanks as part of my backup power and the thing I like about these is that 1 person can handle them + they use same connection 'stuff' as 30lb, 20lb, .... I use a simple hand dolly to move them around and one can even tilt on edge and roll/move short distances.

FYI - in US the tank's dry weight is stamped on the collar and then you can calculate overall weight by gallons put inside or deduce how many gallons are left inside.

Also, I only fill my 100lb tanks to 20gal (they can physically hold 22-23gal) to leave room for expansion since mine sit outside, sometimes in some sunlight / get warm. I notice my local propane supply folks don't seem to know/pay-attention and have overfilled on occasion - which is not good. In one case, it was so full the propane started pushing out as soon as the tank warmed a bit which is hard on overfill valve and propane coming out is fire risk.

 

[rebelrider.mike]

I've been trying not to post lately unless I've made some actual physical progress. This thread is getting pretty long. But there's a couple things I'm just not able to hold back about. First, I finally splurged for a thermal camera got it here on Amazon. I should have got one years ago when I first started playing with 18650s. But they've always been so darn expensive. Anyway, this one was on sale during Black Friday. So far it seems to work as advertised. I haven't verified if the temperatures are accurate, but it definitely sees qualitative differences. And the resolution is good enough that I can recognize what I'm looking at. You can expect some pictures from it in the future.

Next is that it seems Washington will be adopting the 2023 NEC in early 2024. I thought I had until 2026 to get all my electrical work done before the next code adoption. Now I don't know when or if the 2026 code will be adopted or not. So my deadlines I've set for myself are now out the window as they say. Well, no point in sweating it. I'll just start studying the new code and do what needs to be done.

Also, I've arranged for financing to pay for the heat pump installation next year. I'm very excited, as my mother offered to pay for half the cost and loan me the other half interest free. According to my calculations (they used to say that all the time in cartoons when I was a kid, LOL) the money I save by having a heat pump will pay the loan payments entirely, and I shouldn't be impacted financially at all. Which will be incredible if it works out that way.

Lastly, since this thread is getting pretty long, I've added a bullet-point progress report to the very first post so people don't have to wade through all this stuff, but can still be quickly updated on what I've done so far. I hope that will be helpful and convenient for folks.

 

[Korishan]

I finally splurged for a thermal camera got it here on Amazon

Nice!! I'll get one eventually

Next is that it seems Washington will be adopting the 2023 NEC in early 2024. I thought I had until 2026 to get all my electrical work done before the next code adoption. Now I don't know when or if the 2026 code will be adopted or not. So my deadlines I've set for myself are now out the window as they say. Well, no point in sweating it. I'll just start studying the new code and do what needs to be done.

Ooph, that sucks. You should be able to find a comparison guide that shows what's been updated/changed/removed to make the reading a lot easier/faster. If you already have this, could you possibly share the link to the resource?

Also, I've arranged for financing to pay for the heat pump installation next year. I'm very excited, as my mother offered to pay for half the cost and loan me the other half interest free. According to my calculations (they used to say that all the time in cartoons when I was a kid, LOL) the money I save by having a heat pump will pay the loan payments entirely, and I shouldn't be impacted financially at all. Which will be incredible if it works out that way.

Awesome!! Yeah, the heatpumps are very efficient for sure! I actually use less power while cooling my home with the heatpump than I did using 2 fans to pull air from outside across the house and out the other door. AND the house is cooler/drier at the same time! That's a win/win/win for me.
The unit I got is the Prime brand off eBay.
Things to note when looking up the information:
Make sure to check whether the power is fed from the head, or compressor side. Mine is head side, which stinks for me, but ohwell
I would highly recommend getting SEER2 rating >20, and >24 if you can afford it. It'll pay for itself faster the higher the rating is
Definitely get the 220V version for sure. A lot of the models come in both 110 and 220V flavors. So check on that.
AND, most importantly, is to make sure you get coolant that is next gen, which means to stay away from R410A. This is being phased out and replaced with something else. So if you have issues, after 2024/25, you'll pay a lot for any refill if you need it. So look for R-32 or R-454B if possible.

 

[100kwh-hunter]

I would switch everything over if I could. And yeah, ethanol infused fuel causes issues with carbs. Mostly that gummy gucky stuff. not sure where that crap comes from

Not clean enough alcohol.
When in the distilling proses, it starts to drip at 72c and stops at 92C, yes water starts to evaporate at 1C above crystallization point...
But after your cooling (where water goes up and condense goes down refraction column in English?)) you will see the dripping starts at 72C and stops at 78C
Now this part spits out methanol. (and some other lighter alcohol)
Commercial distilleries will keep some methanal in cheap boze/liqueurs, that is your hangover stuff.
Good distillers and good moonshiners will throw this away.
After the helm temperature will reach 82C it will starts dripping again, that is your ethanol, yes the drinkable stuff, hangover free.
It will stop at 88C and starts dripping again at 91C, this will be your heavy alcohols: butanol, propanol, isopropanol(this could also be lighter than methanol dont remember anymore, sorry)
This fase will stop at 95 but the dripping will go on in water vapour.
Water vapor in your alcohol will start to combine at 85C btw.

So your crap is coming from the lighter and i suspect it is coming more from the heavier alcohols...
Water that is present in those alcohols (depending on the amount of minerals and sort of minerals) can also leave some crap.
For sure is the butanol and the propanol alcohols are leaving a lot of carbon residue after burning.
You can filter those ones out with 5 micron or smaller filters.

This write up is done from memory, from the time it was stil "legal" to do moonshine and to do a mix for your gasoline engine car.
So even before my biodiesel experiments! (drove a lot on that stuff, free and co2 very friendly.)

But the temps are correct, but there are 6 different alcohol types, all with there own temp range, on this point i could be wrong. But at the temp of dripping of ethanol i am right. dead sure!
So destill the stuff (extra) and or filter your alcohol and you wont have any crap left.
You want pure ethanol from 82C to 88C
But i think they put in extra stuff like with spiritus to prevent drinking from it. filter and or destill extra.

Sorry did not want to hijack the tread.

With best regards Igor

 

[rebelrider.mike]

The generator inlet wiring is finished!

I picked this particular inlet box because it accepts the twist lock style outlet, and also a threaded collar with a gasket. Making the whole thing that much more water resistant. Now I just need a cable, and maybe a generator.

Since I was working on stuff, I tried out my thermal camera:

Here are the main and sub panels. The two hot spots are AFCI breakers. I don't know how accurate the temperature numbers are yet. I need to find something that has a known temperature to measure. Haven't figured that out yet. Also, I've heard that bare metal sometimes looks hotter than it is because it reflects infrared light same as regular light. So on the thermal camera it's just shiny.

Next is the new generator shutoff box and the ATS:

You can see the main contactor is warm, and you can sort of see behind the numbers that the generator contactor is not. It looks like it might be really hot, but its cooler than the AFCI breakers. You can also see to the right, the Emporia Vue energy monitor doing its best to look creepy.

I still need to install 4 more circuits before the inspection. I doubt it will happen before the 2023 NEC gets adopted. I haven't read through it yet, but I've been hearing that it's mostly changes for organization and language clarification. I hope it's true. The code sorely needs such things.

 

[OffGridInTheCity]

We get 110F ambient each summer.... 61F to 82F, if accurate, would not raise alarms for me - pretty mild

 

[rebelrider.mike]

I "finished" reading through the 2023 NEC and was able to make several updates to my plans. As far as I can tell, nothing major has changed. A lot of stuff got re-written for clarity, and GFCI and AFCI are required pretty much everywhere now. My "DC coupled multimode power control system" is now referred to as a "DC interconnected multimode inverter". Still don't know what to call the sub panel. According to the NEC, there's no such thing, even though I've got two now.

I've updated all my relevant diagrams (and they're also now in widescreen format!) but rather than post them here, I've decided to put them all on the first post of this thread. I'll change them up there as they get updated in the future.

Two of the circuits I need to install in order to close out this phase of the project require some wall construction in the basement. I've purchased a bunch of lumber to cover the block walls so I have an easier surface to attach future stuff to. The new receptacles will be installed on that wall. I forgot to get the floor ankers though, so probably nothing new will happen until after Christmas.

Since it's about the end of the year, I'm thinking of the things I'd like to accomplish next year:

• Finish basement wall. (moderate)
• Install circuit for freezer. (easy)
• Install circuit for convenience receptacles. (easy)
• Install circuit for heat pump. (moderate)
• Move optional load circuits to the new sub panel. (easy)
• Clean up wiring in the basement ceiling and main panel. (moderate)
• Install second Emporia Vue. (easy)
• Purchase generator. (easy, expensive)
• Repair basement door area. (difficult)
• Install weather protection for the inverter and generator. (moderate)
• Have the heat pump installed and ductwork updated. (easy, expensive)
• Install battery and inverter (or at least purchase them). (difficult, expensive)
• Pass inspections. (hopefully easy)
• Start planning for solar. (unknown)

Seems like this may be a bit ambitious. Time (and finances) will tell...

 

[Korishan]

I "finished" reading through the 2023 NEC

you say finished?!?!? Are you suuuuuuurrree???

GFCI and AFCI are required pretty much everywhere now

Yup, saw that one coming

"DC coupled multimode power control system" is now referred to as a "DC interconnected multimode inverter"

LOL semantics, gotta love word jargon

but rather than post them here, I've decided to put them all on the first post of this thread. I'll change them up there as they get updated in the future.

Since it's about the end of the year, I'm thinking of the things I'd like to accomplish next year:

Nice list of To Do's! At least you're keeping yourself busy

 

[rebelrider.mike]

you say finished?!?!? Are you suuuuuuurrree???

Yeah, "finished". Is anyone ever really finished with the code? LOL. Something I've been working on lately is making a spreadsheet of all the requirements that have to be met for my system to pass inspection. A bit of good news: I eliminated Article 710 completely, as it just reiterates 705 when the inverter is in island mode. I could have done that ages ago, but at the beginning of the project I didn't know if I'd be using a grid-interactive inverter or not.

I've been watching Ryan Jackson's videos lately, and it's given me more perspective on the NEC and how its written. I'm surprised they're willing to call inverters inverters. To me that's like calling a Leatherman a pocket knife. Yeah, it's got an inverter in it, but it's crammed with so many other components too. (The inverter that is, not the Leatherman.) Power Control System actually made sense to me. Maybe they didn't want people to confuse it with an Energy Management System.

If I get even half the stuff on my list done next year, I'll be pretty happy.

 

[rebelrider.mike]

Well, unless something wild happens, the money for the inverter and battery just won't be available this year. Still planning on the heat pump installation in April. This also means the solar will be pushed back until sometime after the inverter and battery can happen. 2026 at the soonest.

Speaking of solar... Matt Ferrell and Robert Murrey Smith have both made videos on vertical bi-facial solar panels. I wonder if such a thing would work for my setup. A flatter pergola sure would be easier to build and more stable. And I could paint the top of the pergola white, or maybe some color that absorbs infrared and reflects useful light. But the gaps needed might be too much for my small space. Anyway, it will be at least a couple more years before I can build anything, so I'll keep an eye on how it develops.

 

[rebelrider.mike]

Let's see how I'm doing:

Since it's about the end of the year, I'm thinking of the things I'd like to accomplish next year:

• Finish basement wall. (moderate) Yes!
• Install circuit for freezer. (easy) Yes!
• Install circuit for convenience receptacles. (easy) Yes!
• Install circuit for heat pump. (moderate) Yes!
• Move optional load circuits to the new sub panel. (easy) Kind of.
• Clean up wiring in the basement ceiling and main panel. (moderate) Not yet.
• Install second Emporia Vue. (easy) Not yet.
• Purchase generator. (easy, expensive) Not this year.
• Repair basement door area. (difficult) Not this year.
• Install weather protection for the inverter and generator. (moderate) Not this year.
• Have the heat pump installed and ductwork updated. (easy, expensive) Soon!
• Install battery and inverter (or at least purchase them). (difficult, expensive) Not this year.
• Pass inspections. (hopefully easy) Not yet.
• Start planning for solar. (unknown) Not this year.

It's only half way through the year, but I'm already seeing how things are trending. Anything besides the heat pump that is expensive is right out. I've also got other things competing for my time this year that isn't part of the house energy project.

Some interesting news though: EG4 has come out with an indoor version of their wall battery. Just by moving the terminals to the top makes it much easier for me to install in my limited area. Also, They've just announced their 12kPV inverter. I'm still deciding between that and the 18kPV, but it sure would be easier on my wallet if I can use the new smaller version.

I put together a table of the specs that are important to me to compare:

My color codes are:
Green: good.
Yellow: OK.
Orange: not so good.
Red: deal breaker.

I like the lower idle consumption, and the lower THD. (The grid at my house is around 3%.) And I really like the lower price tag. 200A max charge/discharge for the battery would have been nice, but 167A should be fine. The inverter output seems a bit low, but the panel I'm powering should only see 30A for maybe 1% of the time. And I shouldn't need to be depending on the inverter alone during those times either, since the grid and solar would also be available at those times. So it's probably fine.

Looks like I've got a year or so still to decide, so no rush. Plus you never know what else will be released between now and then.

For now, I'm hoping to get the heat pump and inspection done in the next couple weeks.

 

[OffGridInTheCity]

Nice comparison chart!

 

[rebelrider.mike]

Thanks.

I decided (for the moment) to go with the 12kPV. I've updated my diagrams on the first post of this thread accordingly. Plus a few other details. I've got the down payment for the heat pump paid, and I'm hopeful that installation will happen this coming week. I've also been cleaning out the basement like mad so the HVAC folks can actually get in there to work. My back yard looks like a junk yard trying to have a yard sale.

 

[rebelrider.mike]

Heat pump is installed and working!


The main floor and basement are staying cooler than 3 window A/C units could do, and with less power.

The ATS I bought for the generator circuit didn't pass inspection, but everything else electrical did.

 

[OffGridInTheCity]

Heat pump is installed and working!
View attachment 32161View attachment 32160

The main floor and basement are staying cooler than 3 window A/C units could do, and with less power.

Nice!

We went 4-ton whole house (2600sq ft) hi-end heat-pump in 2019 with the idea of powering it 100% from solar. We live in Zone 4 climate = -1C/30F low and 38C/100F hi. Our heat-pump starts struggling <-1C/30F and starts loosing ground < -7C/20F.

Here's a yearly consumption comparison between 'forced heat-pump' mode and 'efficient mode' (heat-pump + natural gas) in 2022.

Forced heat-pump for 2021 was 9,929kwh for the year. 'Efficient mode' (natural gas secondary heat) was 11,976 kwh (29.31 kwh / therm). So it was less energy for 100% heat-pump but because natural gas is cheap ($1 / therm) the price was similar. And... natural gas has ability to quickly raise house temp at <5C / 40F whereas heat-pump is not so responsive.

Unfortunately, our 15kw PV array only get's us 300-500kwh for the month of December but we need 4x (60kw PV) to heat. Sigh.... property not big enough for 200+ panels.

Will be interested in you're stats once you have some data.

The ATS I bought for the generator circuit didn't pass inspection, but everything else electrical did.

What caused it to fail - did it need ETL certs or something like that?

 

[rebelrider.mike]

When I did my solar estimates I found out that I would only ever produce enough energy about 4 months of the year. The rest, especially December and January, I'll still need the grid. So my endeavors have been to lower my electric bill rather than achieve independence. I'll still be able to go a couple months without the grid if I had to. I'd just have to give up some of the more power-hungry conveniences for a bit.

The ATS was CE listed, and I'd hoped that would be good enough, but it wasn't. When I bought it I could have swore that it was UL or ETL listed. It wasn't until after I had it installed and working that I noticed it was actually CE. I went back to the original advertisement and sure enough, no other listings. So I'm a little disappointed but not surprised. While it's not my first choice, I'll be fine with a UL listed MTS instead. On the bright side, the MTS uses no power at all to function while the ATS uses a few Watts to keep the contacts closed. So the system will be a little more efficient.

There were lots of other details that I wasn't sure would pass inspection. But the inspector was fine with all of them. Like the NEC saying that PVC conduit fittings must be "tight". What constitutes tight? The NEC leaves that up to the AHJ. And my AHJ doesn't answer questions because they're "not in the business of teaching people how to do electrical work". So it's always a guess as to what details will pass until the inspector arrives. In this case, unglued friction fit was sufficient, but they could just as easily have required all the joints to be glued.

Ironically, every inspector I've had has been more than happy to answer questions. But their time is limited, and I don't have access to them until after I've done the work.

 

[OffGridInTheCity]

For 50a @ 240v/120v (US split-phase) I use ETL listed Progressive ATSs - https://www.amazon.com/gp/product/B003VAWNVK/ref=ppx_yo_dt_b_search_asin_title The caveat is they need the 120v part of the 240v split-phase for the relays to operate for some reason.

For 30a @ 120v I use Go-Power ETL ATSs - https://www.amazon.com/gp/product/B00153EYTO/ref=ppx_yo_dt_b_search_asin_title

Not sure is either would work in you're situation but wanted to be encouraging that ETL listed ATS should be available. ATSs are the main way I consume my off-grid solar - absolutely essential for my setup as I wouldn't want to do manual switch-overs every day

 

[rebelrider.mike]

I've ordered both transfer switches. The MTS won't arrive until Friday. It's physically larger and more expensive than the ATS, but will almost certainly pass inspection if I install it. It's UL listed. If I don't use it for this project, I'll almost certainly need it (or a second one) for a future project.
https://www.amazon.com/dp/B008RXTPXK?psc=1&ref=ppx_yo2ov_dt_b_product_details

The ATS arrived today. It's ETL listed. My dilemma here is that the installation instructions show to install the box upside-down:

This would cause the stickers on the box and the internal wiring diagram to be upside down too:

Another issue is that if I install this upside down as per the installation instructions, I'll have enough wire length to make it work. If I install it right side up, I'll either need new wire or I'll need to add wire nuts to several of the wires. That's probably technically acceptable, but I'd rather not do that.

The contactor assembly is off-set inside the box, so I can't just flip it around. I don't know how all this will affect the inspection. So I'm trying now to decide if I should try installing the ATS upside down and risk not passing again, or should I go with the slightly less desirable MTS which is pretty much a sure thing.