Low surge, energy efficient dishwashers for off grid use?

[efficientPV]

full size Miele which pulls about 2035W for the initial 20 mins of cycle while it heats the water

I thought I married a dishwasher but was told otherwise. We run ours almost every day. That is a lot of watts to contend with all at once. I just added a BOSCH ES4 4 gallon hot water tank because I was too lazy to build insulation around my other tank and these little ones are pretty insulated and don't take long to heat with PV. I'm up to 62C by 10am with only 400WH.

 

[Sverige]

I thought I married a dishwasher but was told otherwise. We run ours almost every day. That is a lot of watts to contend with all at once. I just added a BOSCH ES4 4 gallon hot water tank because I was too lazy to build insulation around my other tank and these little ones are pretty insulated and don't take long to heat with PV. I'm up to 62C by 10am with only 400WH.

It’s a lot of watts, for sure, especially since my system is a 4S one. I run my washing machine too, which similarly draws around 2,000W but at the moment only do either when the sun is out so half or more of the power is coming direct from PV and the battery doesn’t get hammered too hard.

Probably with LiFePO4 the battery could supply the 215A or so my inverter wants to draw if I ran the dishwasher from battery with PV off, but I’m not sure all of my cable connections would stay at a happy temperature! Something for me to upgrade over the winter I suppose. Seems like an off grid system is never finished — or is that just me?!

 

[ElectricIslander]

Our LG Inverter Direct Drive Inverter motor washing machine is an off grid wonder due to slow ramp up current draw of it's motor- it's peak draw on the Kill-O-Watt meter is around 800 Watts and for most of it's cycle it draws around 200-300 Watts. A quiet and effective machine.

When washing dishes, to reduce overall electrical energy demand over a dishwasher cycle we run the hot water tap long enough for the water to heat up in the long pipe run from the propane on-demand hot water heater to the dishwasher. That reduces the need for the dishwasher to run the heating element.

I seem to remember that a few years back the "regulators in charge of appliances", whoever they are, mandated that dishwashers must achieve a certain rather high, minimum time duration-temperature threshold in their cycle - sufficient to sanitize dishes. This was baked into the control logic and increases the overall power demand of dishwashers in newer dishwashers.

So, still in search of an older dishwasher with a more efficient motor design (i.e. one wound with a starting winding and capacitor start) but not so new as to have a large built in electrical heating demand .....

 

[Jack Rabbit Off Grid]

Our LG Inverter Direct Drive Inverter motor washing machine is an off grid wonder due to slow ramp up current draw of it's motor- it's peak draw on the Kill-O-Watt meter is around 800 Watts and for most of it's cycle it draws around 200-300 Watts. A quiet and effective machine.

When washing dishes, to reduce overall electrical energy demand over a dishwasher cycle we run the hot water tap long enough for the water to heat up in the long pipe run from the propane on-demand hot water heater to the dishwasher. That reduces the need for the dishwasher to run the heating element.

I seem to remember that a few years back the "regulators in charge of appliances", whoever they are, mandated that dishwashers must achieve a certain rather high, minimum time duration-temperature threshold in their cycle - sufficient to sanitize dishes. This was baked into the control logic and increases the overall power demand of dishwashers in newer dishwashers.

So, still in search of an older dishwasher with a more efficient motor design (i.e. one wound with a starting winding and capacitor start) but not so new as to have a large built in electrical heating demand .....

What’s that bad boy use in water for a load?

 

[Sverige]

Our LG Inverter Direct Drive Inverter motor washing machine is an off grid wonder due to slow ramp up current draw of it's motor- it's peak draw on the Kill-O-Watt meter is around 800 Watts and for most of it's cycle it draws around 200-300 Watts. A quiet and effective machine.

Sounds great for avoiding too high peak power - do you know how many Wh in total a cycle uses? I guess it must run the heater longer at this lower power than a 2kW washing machine does, but the overall Wh should be similar it two different machines are heating the same amount of water to the same temp.

 

[ElectricIslander]

Sounds great for avoiding too high peak power - do you know how many Wh in total a cycle uses? I guess it must run the heater longer at this lower power than a 2kW washing machine does, but the overall Wh should be similar it two different machines are heating the same amount of water to the same temp.

Sorry, due to thread drift was talking about our LG clothes washing machine which doesn't heat water at all (unlike a dishwasher). But next time we do a load I'll measure the total cycle Watt-hrs used to wash a load of clothes.

 

[chess-equality]

I'd say inverter-type appliances are much more efficient, have lesser power draw, and don't produce large inrush currents.

We have 2 inverter-type aircon units, both 1.5Hp, a Kolin (local brand) window-type rated at 1280w, and an LG portable rated at 1370w. The LG portable says it uses "dual inverter" technology, but I'm not sure if it's only a marketing gimmick.

LG 12,000 BTU DUAL Inverter Portable Air Conditioner | LG Philippines

Get more information on the LG PA150DLX. Click for pictures, reviews, and tech specs for the LG 12,000 BTU DUAL Inverter Portable Air Conditioner

www.lg.com

The Kolin normally draws 500-700w, but when it gets cold enough it powers down to around 200-300w. I have not measured yet the LG's, but since the Kolin is 6 years old now, the LG should be much more efficient, being newer at 1.5 years old.

We also have a Panasonic inverter-type fridge, 8 cu. ft., rated at 85w, but normally draws only around 50w. During late nights or when not opened for prolonged periods of time, it powers down to 0w.

NR-BP230VD 2-door Top Freezer - Panasonic Philippines

Explore the Panasonic NR-BP230VD - 2-door Top Freezer

www.panasonic.com

The Kolin aircon and the fridge are connected to our (power) inverters, 3.5kw (24v) and 1kw (12v), respectively, and the batteries can start them off just fine, no hiccups.

 

[pollenface]

Or, wash by hand seems simpler.

Heck yeah ;D

 

[Llaves]

One of my neighbours spent more on “energy efficient” appliances than it cost for my entire power system and “normal” appliances.

Keep that in mine if you are paying a large premium for efficiency.

Similar to spending an extra $100k for passivhaus style building. Way better to build normally and spend the extra on your power system.

This is really important advice. When I built my off-grid house 15+ years ago PV was $4/W just for the panels. But even at that price it was cheaper to add panels and buy a "normal" fridge than to pay the premium for a super-efficient fridge designed for off-grid use. On top of that, I had a wider range of choices to pick from. With panels at 1/10 that cost today, the decision is even more obvious.

 

[ElectricIslander]

This is really important advice. When I built my off-grid house 15+ years ago PV was $4/W just for the panels. But even at that price it was cheaper to add panels and buy a "normal" fridge than to pay the premium for a super-efficient fridge designed for off-grid use. On top of that, I had a wider range of choices to pick from. With panels at 1/10 that cost today, the decision is even more obvious.

True, unless you live in the eternally cloudy PNW or other parts of the world where winter sun is non-existent and the balance of economics of energy efficiency vs cost of battery storage shifts dramatically .....