First...it doesn't seem like there's an Ecoflow type thread here, but LMK if there is and I'm just an idiot and can't figure out basic search parameters.
Anyway, I took delivery of two EcoFlow ∆ Pro units last month. I was smart enough to buy them right when they went live so I missed the Costco deal and instead paid an extra grand or something to buy them direct from Ecoflow, but...whatever, I have them now...and everyone has to pay the Stupid Tax sometime, right? So far I'm happy with them. Ive only had to use them twice in and only for short periods, but overall they seem to have a good amount of flexibility in use, and the app is user friendly enough and lets me set things like max charge rate, min/max SOC, etc.
Here's an unremarkable pic of what happens to be my batteries (as opposed to a similar, if not better composed stock photo), mostly because people on the internet seem to like pictures. Sorry there's no cat in there. They're assholes anyway. I'll tell you what you can do with a cat and a fully charged battery...
(Also, calm down, we have a few feral cats on our property)
I intend to use these as a whole house, 240V backup for when my power goes out...which, somewhat surprisingly/unfortunately, occurs with remarkable frequency even just barely in the hills above Silicon Valley where I live. Most are hours long, though we've had days long outages as well (mostly PGE "afraid to burn it all down" outages). Anyway, we've played the extension cord game for a few years and its finally time to have something more comprehensive. We have two small kids and really just want something simple and with very little compromise to our daily activities. FTR I did investigate more traditional generator transfer switches, but the architecture I've come up with seems cleaner and easier to implement, at least to me.
The main reason I got two batteries is because Ecoflow sells (or at least, will sell) a bridge cable to combine the output of the two 120V batteries to a proper 240W/30A. For some sizing verification, scrolling through my Sense data (anyone know how to actually export from Sense?) tells me ~7kW easily covers what I'd consider 'cognizant' peak loading. So far this winter my absolute peak load was 13.1kW, but that was layering my dryer (wifey likes warm laundry so whenever she's doing the laundry its drawing 5-6kW or something), my recently installed 4 zone split (that surges to 3kW but is usually in the 1-2kW range when running) that replaced my LP furnace for heating (and also added air conditioning because, you know, global warming), and cookies baking in the main oven (our microwave is also a convection oven so we usually use that for oven duty). Hand waving all that around I figure as long as we're barely thinking about time shifting the big loads we can pretty easily keep it under 7kW. Note that we've got a tankless water heater right now that will eventually be swapped for a heat pump, so that would be slightly more load consideration...but that's not a "soon" kind of thing so I'm not going to worry about it right now.
In order to make this work from a whole house perspective I put a two way disconnect switch in front of my service panel. Save for labels (and some paint...) my house is now wired such that power goes directly from the meter into the disconnect switch so I can swap the input to the service panel between municipal power and 'generator' power. Worst part of this whole setup is the old Zinsco main breaker under the meter (that's been there since the house was built in 1960)...
Certainly 7kWh from the two batteries isn't going to last too long, and more EcoFlow batteries (to say nothing of a can't-buy-one-even-if-i-wanted Powerwall solution) seems like an irresponsible financial solution to the problem of providing backup power, so I'm going to put a small generator behind the two batteries to ensure I always have enough energy, specifically a Champion 2500 dual fuel inverter. This one operates at 1800W, so I'll throttle my Ecoflow charge rates to 800W each for 1600W load (you can only adjust in 200W increments) and the idea is that the generator will manage consumption while the batteries handle the peak loads. I prefer the idea of using the ~smallest (and ostensibly, quietest) generator for this application rather than a larger one that could max rate charge the batteries at 1.6kW x 2, mostly because I feel better about leaving a small generator running overnight, but also because I believe its ultimately going to lead to better overall fuel efficiency. While I have yet to put this into practice, my current thought is that during outages I'll have the ability to toggle the gennie on and off when I'm awake (based on battery SOC), and I'll just leave it running overnight on the nights where we won't be able to make it till morning on just 7kWh of battery power.
Again looking to data
eek to verify my generator sizing, save for an anomaly day of 60kWh usage my peak daily winter consumptions never go above 45kWh--and again that's zero cognizance of total consumption. Its also worth noting that my peak daily split consumption is 33.9kWh and usually average in the 20-25 range. Daily generator math is 1600W x 24h = 38.4kWh, and that feels like its going to do the job as long as we're giving a passing thought to our total daily consumption. Note that I also have a wood stove to offset BUTs if temperatures go particularly cold during a power outage.
Its with sharing that dual fuel (and I guess more concisely, propane) is kind of a self-imposed requirement for me. For one, **** gas, for B **** storing gas, and for gamma, I have a 250gal LP tank that, after uninstalling my furnace, isn't doing anything but supplying my water heater anyway. Even without having the tank refilled there's a LOT of outage hours that can be accommodated. This generator won't be quite as seamless as the EcoFlow smart generator option, but its also way cheaper and the Ecoflow generators are gasoline with no current roadmap to propane.
From a switchover process perspective, what I'm planning on doing is just having another two way switch (just a toggle, not a full disconnect box) that I manually flip when the power goes out to switch the battery inputs from "house" to "generator". With city power I'd leave the batteries plugged into the house so they stay topped off at 90% SOC waiting for the next outage, but if I don't flip their inputs off the house they'll end up perpetually charging themselves until house loads (plus, DC/AC/DC/AC inefficiencies). I'd love to have something a little more automated/foolproof as that ends up being (I think) the only step in my switchover process that if missed would lead to a bit of a feedback loop rather than a hard short...so if anyone has any ideas I'm all ears.
Finally, its worth sharing that my house isn't really solar friendly. Solar isn't a hard no, but it isn't a priority. In the winter months I get ~2 hours of unshaded sun on a fairly small rooftop area, and there's really no option for ground mounted panels. The Ecoflows do have Solar/DC inputs so I guess that's better than bad (!= wood?), though I don't think this architecture is particularly compatible with simply adding solar.
Anyway, I took delivery of two EcoFlow ∆ Pro units last month. I was smart enough to buy them right when they went live so I missed the Costco deal and instead paid an extra grand or something to buy them direct from Ecoflow, but...whatever, I have them now...and everyone has to pay the Stupid Tax sometime, right? So far I'm happy with them. Ive only had to use them twice in and only for short periods, but overall they seem to have a good amount of flexibility in use, and the app is user friendly enough and lets me set things like max charge rate, min/max SOC, etc.
Here's an unremarkable pic of what happens to be my batteries (as opposed to a similar, if not better composed stock photo), mostly because people on the internet seem to like pictures. Sorry there's no cat in there. They're assholes anyway. I'll tell you what you can do with a cat and a fully charged battery...
(Also, calm down, we have a few feral cats on our property)
I intend to use these as a whole house, 240V backup for when my power goes out...which, somewhat surprisingly/unfortunately, occurs with remarkable frequency even just barely in the hills above Silicon Valley where I live. Most are hours long, though we've had days long outages as well (mostly PGE "afraid to burn it all down" outages). Anyway, we've played the extension cord game for a few years and its finally time to have something more comprehensive. We have two small kids and really just want something simple and with very little compromise to our daily activities. FTR I did investigate more traditional generator transfer switches, but the architecture I've come up with seems cleaner and easier to implement, at least to me.
The main reason I got two batteries is because Ecoflow sells (or at least, will sell) a bridge cable to combine the output of the two 120V batteries to a proper 240W/30A. For some sizing verification, scrolling through my Sense data (anyone know how to actually export from Sense?) tells me ~7kW easily covers what I'd consider 'cognizant' peak loading. So far this winter my absolute peak load was 13.1kW, but that was layering my dryer (wifey likes warm laundry so whenever she's doing the laundry its drawing 5-6kW or something), my recently installed 4 zone split (that surges to 3kW but is usually in the 1-2kW range when running) that replaced my LP furnace for heating (and also added air conditioning because, you know, global warming), and cookies baking in the main oven (our microwave is also a convection oven so we usually use that for oven duty). Hand waving all that around I figure as long as we're barely thinking about time shifting the big loads we can pretty easily keep it under 7kW. Note that we've got a tankless water heater right now that will eventually be swapped for a heat pump, so that would be slightly more load consideration...but that's not a "soon" kind of thing so I'm not going to worry about it right now.
In order to make this work from a whole house perspective I put a two way disconnect switch in front of my service panel. Save for labels (and some paint...) my house is now wired such that power goes directly from the meter into the disconnect switch so I can swap the input to the service panel between municipal power and 'generator' power. Worst part of this whole setup is the old Zinsco main breaker under the meter (that's been there since the house was built in 1960)...
Certainly 7kWh from the two batteries isn't going to last too long, and more EcoFlow batteries (to say nothing of a can't-buy-one-even-if-i-wanted Powerwall solution) seems like an irresponsible financial solution to the problem of providing backup power, so I'm going to put a small generator behind the two batteries to ensure I always have enough energy, specifically a Champion 2500 dual fuel inverter. This one operates at 1800W, so I'll throttle my Ecoflow charge rates to 800W each for 1600W load (you can only adjust in 200W increments) and the idea is that the generator will manage consumption while the batteries handle the peak loads. I prefer the idea of using the ~smallest (and ostensibly, quietest) generator for this application rather than a larger one that could max rate charge the batteries at 1.6kW x 2, mostly because I feel better about leaving a small generator running overnight, but also because I believe its ultimately going to lead to better overall fuel efficiency. While I have yet to put this into practice, my current thought is that during outages I'll have the ability to toggle the gennie on and off when I'm awake (based on battery SOC), and I'll just leave it running overnight on the nights where we won't be able to make it till morning on just 7kWh of battery power.
Again looking to data
eek to verify my generator sizing, save for an anomaly day of 60kWh usage my peak daily winter consumptions never go above 45kWh--and again that's zero cognizance of total consumption. Its also worth noting that my peak daily split consumption is 33.9kWh and usually average in the 20-25 range. Daily generator math is 1600W x 24h = 38.4kWh, and that feels like its going to do the job as long as we're giving a passing thought to our total daily consumption. Note that I also have a wood stove to offset BUTs if temperatures go particularly cold during a power outage. Its with sharing that dual fuel (and I guess more concisely, propane) is kind of a self-imposed requirement for me. For one, **** gas, for B **** storing gas, and for gamma, I have a 250gal LP tank that, after uninstalling my furnace, isn't doing anything but supplying my water heater anyway. Even without having the tank refilled there's a LOT of outage hours that can be accommodated. This generator won't be quite as seamless as the EcoFlow smart generator option, but its also way cheaper and the Ecoflow generators are gasoline with no current roadmap to propane.
From a switchover process perspective, what I'm planning on doing is just having another two way switch (just a toggle, not a full disconnect box) that I manually flip when the power goes out to switch the battery inputs from "house" to "generator". With city power I'd leave the batteries plugged into the house so they stay topped off at 90% SOC waiting for the next outage, but if I don't flip their inputs off the house they'll end up perpetually charging themselves until house loads (plus, DC/AC/DC/AC inefficiencies). I'd love to have something a little more automated/foolproof as that ends up being (I think) the only step in my switchover process that if missed would lead to a bit of a feedback loop rather than a hard short...so if anyone has any ideas I'm all ears.
Finally, its worth sharing that my house isn't really solar friendly. Solar isn't a hard no, but it isn't a priority. In the winter months I get ~2 hours of unshaded sun on a fairly small rooftop area, and there's really no option for ground mounted panels. The Ecoflows do have Solar/DC inputs so I guess that's better than bad (!= wood?), though I don't think this architecture is particularly compatible with simply adding solar.
