Brucey
Solar Wizard
It's the size of your battery not the output of your inverter?
Need a way to bottle or can excess solar production.
- Thread starter Mattb4
- Start date
ScrotpusGobbleBottom
Corn Pop was a bad dude.
Isnt legionnaires disease a concern with this setup? I was always under the impression that you do not want stagnant water in a water heater. I was researching how to save power on my own water heater and came across this information. It seems even 120 degrees F is not quite hot enough to kill it.
dougbert
Solar Addict
I use the hot water every day for showers, clothes and dish washing. It is INLINE with my normal water heater - upstream from it
water won't stay hot in the heaters for long anyway. I have wrapped insulation around them and extra on top,
the diversion is ON as I type this right now heating the water
pollenface
Solar Addict
I don't see excess solar as being a problem.
I really like mppts which have a float relay function so you can automatically trigger opportune loads once batteries are floating.
I really like mppts which have a float relay function so you can automatically trigger opportune loads once batteries are floating.
dougbert
Solar Addict
I have 4 charge controllers, one for each array. I use one of 4 as the controller of the water heater
Each one has an "AUX" port that has table of trigger operations. One of which is FULL BATTERY. I use that to enable a 12v auto relay, which in turns enables the SSRs, one SSR for each leg
just took some pics of it
the box and 10 awg feeding it. the new 3000 watt coils on the right
inside of box. wired for 120v only at the moment
get 2 of this SSR crydom D2425 $50 on ebay to $70 at other stores
I added 3 AC LEDs, RED means ON, first green on left means 1st water heater is hot, 2nd green on right means 2nd water heater is complete
#10 awg wire again. Added screen heat vent on top
2 pole 20 amp breaker, supports the 2000 watt and will support the 3000 watt coils
top of 1st water heater
bottom of 1st water heater with 1 leg cascading out and back to the box. then it and the other leg go back to 2nd water heater. the 2nd is behind the first. both bolted to wall
I need to diagram the wiring and verify I did things correctly
2nd heater is "back in there"
Each one has an "AUX" port that has table of trigger operations. One of which is FULL BATTERY. I use that to enable a 12v auto relay, which in turns enables the SSRs, one SSR for each leg
just took some pics of it
the box and 10 awg feeding it. the new 3000 watt coils on the right
inside of box. wired for 120v only at the moment
get 2 of this SSR crydom D2425 $50 on ebay to $70 at other stores
I added 3 AC LEDs, RED means ON, first green on left means 1st water heater is hot, 2nd green on right means 2nd water heater is complete
#10 awg wire again. Added screen heat vent on top
2 pole 20 amp breaker, supports the 2000 watt and will support the 3000 watt coils
top of 1st water heater
bottom of 1st water heater with 1 leg cascading out and back to the box. then it and the other leg go back to 2nd water heater. the 2nd is behind the first. both bolted to wall
I need to diagram the wiring and verify I did things correctly
2nd heater is "back in there"
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Nobodybusiness
Solar Sponge.
Made sense back in 2010 when I did it but now if you don’t sell and upgrade you fall behind on the difficulty.
That was using ASIC miners.
Never tried with GPU miners.
DIYrich
Solar Wizard
Direct air carbon capture.
Figure out a way to sell excess power to your neighbor.
Figure out a way to sell excess power to your neighbor.
OffGridInTheCity
Solar Wizard
I've gone round and round in my thinking on this over the last several years - the answer is 'a battery'. Lately, I've been dreaming of a container with 60 used EV batteries to store up 4000kwh during summer for use during winter - 1 cycle / year so used EV batteries should last a long time
ScrotpusGobbleBottom
Corn Pop was a bad dude.
YES! You and me both!I've gone round and round in my thinking on this over the last several years - the answer is 'a battery'. Lately, I've been dreaming of a container with 60 used EV batteries to store up 4000kwh during summer for use during winter - 1 cycle / year so used EV batteries should last a long time
1 year of backup?!? Your home must see some really lousy weather. Reminds me of growing up near Seattle and having to be told what the strange glowing ball of fire in the sky was one day. Terrifying sight to a young kid.I've gone round and round in my thinking on this over the last several years - the answer is 'a battery'. Lately, I've been dreaming of a container with 60 used EV batteries to store up 4000kwh during summer for use during winter - 1 cycle / year so used EV batteries should last a long time
Problem with all that batteries is it would take a commercial solar farm to charge them in a reasonable time.
Brucey
Solar Wizard
1 battery cycle per year. Say calendar life of 15 years. So we've left say 3000-6000 cycles on the table.
DIYrich
Solar Wizard
Self discharge rate of lfp is 3-4% per year. On 4000kwh, that is 80kwh (assuming 1/2 year) of power.
I've gone round and round in my thinking on this over the last several years - the answer is 'a battery'. Lately, I've been dreaming of a container with 60 used EV batteries to store up 4000kwh during summer for use during winter - 1 cycle / year so used EV batteries should last a long time
Same here. A 1MWh power container should see me through winter without having to run a generator at all. With cells approaching $50 per kWh, it's really entering the realm of reality. Less than a decade ago, cell prices were over $300 per kWh.
Doggydogworld
Solar Enthusiast
- Joined
- Aug 29, 2022
- Messages
- 366
Where do you find Model 3 packs for $2k? Most I see under 5k are damaged.
Seen one sell for $3k on Ebay. Buy direct from wrecked car lots.
I'm a bit south of Seattle, and last year there was a period where my 1.6kw of panels took three weeks to harvest 4kwh. There's a reason nearly everyone around here takes vitamin D supplements all winter, and some of us all year.
Exciting times. Serious power storage is becoming available for a lot of people.
wpns
Solar Joules are catch and release
Wind doesn’t scale linearly like solar does, small wind generators will almost certainly disappoint
Don't go with small wind turbines unless you have absolutely perfect conditions. It will be a disappointment otherwise. You're dealing with two fundamental issues:
- The Betz Limit
- The Power in Wind equation
The Betz Limit is basically a theoretical number of the maximum efficiency you can possibly get. At most, only 59.3% of the kinetic wind energy can be used to spin the turbine and generate electricity. Remember this is a theoretical limit; in practice, you're going to be closer to 40%.
The Power in Wind equation is given as:
P = 1/2 x ρ x A x V³
Where:
P = power in Watts
ρ = air density (kg/m³, at about 1.2 at sea level)
A = Swept area of the blades (m²)
V = Velocity of the wind
So, no matter how good your turbine is, you will get in practice at most 40% of the wind energy converted to electricity. To capture the wind energy in the first place, you have two variables to increase (one in your control, the other not): swept area and wind velocity. The smaller you make the turbine, the faster you need to spin to make any meaningful energy. The only variable you control is the swept area, which means making the blades as big as possible. Also notice that the velocity is cubed in that equation, so you'll generate much, much less power at low wind speeds.
In other words, small wind turbines don't work except in ideal situations because physics.
Quite aware that small scale wind is very far from ideal. There's just so much time here where there simply isn't sun. As I said before, this past winter 1.6kw of panels took three WEEKS to harvest 4kwh of power. A wind turbine harvesting an average of 10w 24/7 would have done 5kwh in that same time.
According to this calculator:
Wind Turbine Calculator [HAWT and VAWT]
The wind turbine calculator finds the power output, efficiency, RPM, torque, and revenue of a wind turbine (either HAVT or VAWT).
www.omnicalculator.com
A 5ft diameter and 5ft tall VAWT in a 5mph breeze(very doable here) could possibly harvest 15w during that time, so it's doable.
Would have to crunch the numbers and see if I could build a functional VAWT for anything approaching the cost of a pallet of cheap used panels and some lumber for a ground mount.
I know your pain - I'm at 63 degrees north. My 15kW array makes 0 kWh in the middle of winter. However, with wind you also have maintenance. I assume you, like me, are in an area where you have snow and ice in winter? A small turbine will ice up and lock up from snow build up in no time.
5kWh is very easy to make with a generator. With a Diesel generator, you could even make your own fuel with waste vegetable oil (I do this to get through winter).
HalfBaked
Ever the student
This makes me envision a future where electricity is used as "currency". I could see people carrying small, light, high capacity batteries and buying things with them.
Later, it morphs into a central bank and a lithium standard is adopted. Cash is printed. Batteries will be rumored to be kept in a guarded vault in Kentucky.
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