Feast or Famine, The off grid solar dilemma.
- Thread starter Mattb4
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robby
Photon Vampire
- Joined
- May 1, 2021
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I have the same issue. I could buy 10KWh more of batteries and nullify my grid usage throughout 6 months of the year but for the other six months they will not be charging enough to make a dent in my grid usage.
I Ran the numbers in a spreadsheet and the ROI is just not there to pay for the batteries.
This always make me wonder: why do you need 40kWh/day when trying to go off-grid? I use maybe 2kWh a day to keep the systems running, 5 to 6 with all the bells and whistles in winter. This is a normal house, with running water, flushing toilet, fridge, dishwasher, washer and dryer, etc.
Of course, heating is not done electrically in winter - that's what the wood gasification burner and masonry fireplace is for. In summer, I use my excess solar to process wood (electric tools) for winter use. I also make biodiesel in summer, and don't burn wood (even if it's still cold) from somewhere March onwards because I can use a heat-pump and plain resistive electric water boiler in summer (heat pump cools then).
If you rely purely on electric for heating (even with a heat pump), doing so off-grid in places tat experience real winter is nearly impossible.
Nobodybusiness
Solar Sponge.
Sounds like we had similar careers prior to civilian life.
Different time. Today we are deprived if the smart phone loses signal.
Being of an earlier generation and growing up rural I look at stuff like electricity as a marvel to be cherished. We always turned off lights when leaving a room. Never ran things unless really needed and overall practice conservation.
Nobodybusiness
Solar Sponge.
What do you consider a real winter?
MrM1
I'm Here, But I'm Not All There
Is that some kind of Magic Dryer? ? Mine uses 5000 watts an hour. That's the only thing left on grid. I'll use a clothes line in a $HTF
MrM1
I'm Here, But I'm Not All There
Him? Think Artic Circle or nearly ?
That's what I was thinking too. ? My little 120 one uses less then 1500 watts (a little more considering inverter loss). Although takes like 2+ hours to dry a load. It's a washer ventless dryer combo machine. It "recycles" some of the heat by not having vent. It has a disadvantage of having to clean out the lint though as there is any lint screen, but you don't have to transfer your clothes from the washer to dryer!
Nobodybusiness
Solar Sponge.
I ask because I am all electric and use HP forHim? Think Artic Circle or nearly ?
My heat.
Now last December I did have to break out the Generator for a bit because it was so rainy.
It got down to 4F degrees here.
OzSolar
Whatever you did, that's what you planned.
It's still almost mind boggling to me that we talk about running AC (heat pumps) off of solar PV like it's commonplace. Two thing have changed big time since I started dabbling with this stuff back in the 90's.
1) Modules used to cost $4/watt and now with a bit of patience you can get ~5kW of brand new modules delivered to your door (or at least the end of your driveway) for less than $2,500. Most people can run everything they need to 90% of the time with around 5kW of PV or less.
2) Mini Splits are a relatively new thing in my world. For less than $1,000, YouTube and the help of a buddy with some HVAC tools most people can cool and heat a substantial part of thier house with an additional 1 KW of PV or less. (granted that's likely an unserviceable throwaway mini split)
edit to fix typos
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MrM1
I'm Here, But I'm Not All There
Well Upnorth according to his about page is at 63° North, Finland
5kW - wow...
Probably not magic, but I'm guessing just a modern heat-pump dryer like the one below... manual says it draws 645W and dries 4Kg load in just over 1kWh, or 8Kg load with 1.8kWh - so assume it will take 2 to 3 hours.
WTH85222GB | Bosch Heat Pump Tumble Dryer | 8kg | ao.com
This WTH85222GB Bosch heat pump tumble dryer can hold 8kg of laundry and comes with AutoDry tech and SensitiveDrying system that leaves clothes wrinkle-free.
ao.com
MrM1
I'm Here, But I'm Not All There
Yeah that's what I'd think ... Or Coal Fired ?5kW - wow...
Probably not magic, but I'm guessing just a modern heat-pump dryer like the one below... manual says it draws 645W and dries 4Kg load in just over 1kWh, or 8Kg load with 1.8kWh - so assume it will take 2 to 3 hours.
WTH85222GB | Bosch Heat Pump Tumble Dryer | 8kg | ao.com
This WTH85222GB Bosch heat pump tumble dryer can hold 8kg of laundry and comes with AutoDry tech and SensitiveDrying system that leaves clothes wrinkle-free.
Propane
I wish mine used 645 watts. Mine is 4800 or 5000 watts. Hungry thing for sure.
But on the flip side it dries the crap out of clothes. My parents have the new fancy stackable ones and probably are the low wattage kind. Doesn't dry clothes worth a flip compared to my dinosaur
But on the flip side it dries the crap out of clothes. My parents have the new fancy stackable ones and probably are the low wattage kind. Doesn't dry clothes worth a flip compared to my dinosaur
Heat pump dryer (Candy Smart Pro). I'm running it right now - consumption about 300W with a couple of smaller spikes. Uses about 1.5kWh for a full load.
That's only a 8 kg dryer though. Not tiny but might be too small for people that don't like to do laundry a lot. A larger capacity heat pump dryer would use more. That would be the perfect dryer for a medium RV.I wish mine used 645 watts. Mine is 4800 or 5000 watts. Hungry thing for sure.
But on the flip side it dries the crap out of clothes. My parents have the new fancy stackable ones and probably are the low wattage kind. Doesn't dry clothes worth a flip compared to my dinosaur
The one where it gets cold (-20C), dark (2 to 3 hours of light at most) and sees tons of snow.
SilverbackMP
Solar Addict
- Joined
- Apr 4, 2022
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- 1,011
I just put in a new Speed Queen set for my mom and went with with a gas dryer. Dries like a middle eastern wind storm. Was thinking about trying out an inverter type, but think I will go with propane until they ban em.I wish mine used 645 watts. Mine is 4800 or 5000 watts. Hungry thing for sure.
But on the flip side it dries the crap out of clothes. My parents have the new fancy stackable ones and probably are the low wattage kind. Doesn't dry clothes worth a flip compared to my dinosaur
MrM1
I'm Here, But I'm Not All There
?How much clothes could a Wind Storm dry if a wind storm could dry clothes? ?
(to the tune of Woodchuck)
?
houseofancients
Solar Wizard
sonoff , controller by home assistant
Never knew such a thing existed. I have to research if there is any available in the US market. My ~28 year old 240vAC dryer is an energy hog but it does dry things (a typical load in under 40 minutes). I can not power it from my PV so it like my electric range ( almost never use it with all my countertop cookers/ovens) remain grid powered. Like others mentioned a clothes line can handle clothes dryer duties if needed.5kW - wow...
Probably not magic, but I'm guessing just a modern heat-pump dryer like the one below... manual says it draws 645W and dries 4Kg load in just over 1kWh, or 8Kg load with 1.8kWh - so assume it will take 2 to 3 hours.
WTH85222GB | Bosch Heat Pump Tumble Dryer | 8kg | ao.com
This WTH85222GB Bosch heat pump tumble dryer can hold 8kg of laundry and comes with AutoDry tech and SensitiveDrying system that leaves clothes wrinkle-free.
Steve_S
Offgrid Cabineer, N.E. Ontario, Canada
Interesting thread...
I'm offgrid (grid is not here) with Solar.
Daily average usage is 3-3.5kWh summer or winter.
No AC System, home never goes above 26C/79F even during heatwaves over 40C/105F due to home design.
Heating in winter is maintained at 25C/77F. This is Radiant Heat within a Frost Protected Slab Foundation. Presently heated using a Propane On-Demand Heater (to be replaced with Hydronic Heat Pump). Wood stove is in place and used only rarely.
During Summer I am in FLOAT most often by 11:00-12:00 AM then Float services all ongoing demands as the battery bank balances itself.
During Winter here (Algonquin Park Ontario Canada) I do not often see Float but I do have 10 Days of Energy Storage and for the most part that is fine with only rare generator runs to charge. Last Winter was our darkest in 80 Years so more generator time was used. That is being addressed with the addition of another 2400W Array and Midnite Classic-150 set for a better Winter Angle (fixed ground mount).
Much like @upnorthandpersonal my home was designed & built for purpose and THAT makes a tremendous difference in operational overhead. The first hint anyone get's that this house is different is the fact that roof is over 30cm/1 foot thick (Thermally Broken, Cool-Roof System) and everyone notices the super thick facia and then they notice the other details... Not many homes have 24cm/9" thick walls ;-) (Thermally broken walls with Rain-Screen Siding system using Live Edge White Cedar).
I do not consider my Energy Generation "excess" as an issue, I prefer to have the excess generation capability as my batteries are always happily charged. With the Sunhour shortage last year, my new array will address that and more. While this upgrade may seem more than I need, it is also part of the Last Upgrade Stage for when I switch to 48V Batteries & 240V SplitPhase from my current 120V system.
I'm offgrid (grid is not here) with Solar.
Daily average usage is 3-3.5kWh summer or winter.
No AC System, home never goes above 26C/79F even during heatwaves over 40C/105F due to home design.
Heating in winter is maintained at 25C/77F. This is Radiant Heat within a Frost Protected Slab Foundation. Presently heated using a Propane On-Demand Heater (to be replaced with Hydronic Heat Pump). Wood stove is in place and used only rarely.
During Summer I am in FLOAT most often by 11:00-12:00 AM then Float services all ongoing demands as the battery bank balances itself.
During Winter here (Algonquin Park Ontario Canada) I do not often see Float but I do have 10 Days of Energy Storage and for the most part that is fine with only rare generator runs to charge. Last Winter was our darkest in 80 Years so more generator time was used. That is being addressed with the addition of another 2400W Array and Midnite Classic-150 set for a better Winter Angle (fixed ground mount).
Much like @upnorthandpersonal my home was designed & built for purpose and THAT makes a tremendous difference in operational overhead. The first hint anyone get's that this house is different is the fact that roof is over 30cm/1 foot thick (Thermally Broken, Cool-Roof System) and everyone notices the super thick facia and then they notice the other details... Not many homes have 24cm/9" thick walls ;-) (Thermally broken walls with Rain-Screen Siding system using Live Edge White Cedar).
I do not consider my Energy Generation "excess" as an issue, I prefer to have the excess generation capability as my batteries are always happily charged. With the Sunhour shortage last year, my new array will address that and more. While this upgrade may seem more than I need, it is also part of the Last Upgrade Stage for when I switch to 48V Batteries & 240V SplitPhase from my current 120V system.
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