Aquanta Networked Water Heater Controller

[redpoint5]

My apartment was recently outfitted with an Aquanta networked water heater controller which monitors which times of day hot water is used, and attempts to schedule heating during off-peak hours and during normal use hours, while limiting heating during peak hours and durings times of day when hot water isn't used.

I sent an email to the utility asking for more data, or access to the data through the app, and received this response:

My name is Nathan, I am a Multifamily Water Heater Demand Response Specialist, and I would be happy to help you with your question. The smart device installed on your water heater is connected with PGE’s Multi Family Water Heater program. The device creates savings for PGE by allowing for water to be heated at specifically determined times, which helps PGE prioritize the use of lower cost and greener energy sources, and in doing so helps them to avoid building new power plants, which should in turn help customers by keeping rates low. However, this device isn’t expected to provide significant energy savings for individual customers such as yourself, as it won’t reduce your hot water usage. As such, the device does not connect to a smartphone app for customers to control.

I'm wondering if it saves any energy at all, considering off-peak is when we don't need hot water.

PGE doesn't have tiered rates, so it seems unlikely that this would save any money. Seems a waste really.

[oil pan 4]

Sounds like the water heater timer reinvented.
As least water heater timers supposedly saved some energy by not allowing the water heater to maintain set point for most of the day when no one is using hot water.

[ksa8907]

I can see where it would help when trying to load balance the grid when used on these large water heaters/boilers. Much like the units that go on a/c compressors.

I doubt the purpose is to save the end user money.

[redpoint5]

I doubt it saves anyone any money. The units themselves are about $125 each, then the cost of the tech to install them, then ongoing maintenance and administrative costs...

My hot water heater is tiny at the apt. It gives maybe 10min of hot water at the 2.5 gal showerhead flow-rate. I've since installed a 2 gal flow head because the 2.5 had a garbage pattern and didn't have a wand. Hot water lasts a bit longer now. Perhaps it's a 10 gallon tank?

There is a certain percentage of the utility bill that goes towards efficiency programs, and my guess is the utility has to use it or lose it. This is probably just a program designed to consume funds they have already received. If they were really interested in lowering consumer bills, they would just charge me less in the first place.

[ksa8907]

They installed them on individual, residential sized water heaters? That would be a waste. Maybe its a stripped down version, at the least, I really doubt the utility paid retail price.

I suspect you are correct about the energy efficiency programs.


Maybe they plan to report your water heating energy usage on your bill?

[redpoint5]

Originally Posted by ksa8907

They installed them on individual, residential sized water heaters? That would be a waste. Maybe its a stripped down version, at the least, I really doubt the utility paid retail price.

I suspect you are correct about the energy efficiency programs.


Maybe they plan to report your water heating energy usage on your bill?

Well my estimate of heater size was way off; it's a 47 gallon tank. Seems small hanging in the small laundry closet of the apt. No idea why I begin to run out of hot water after 10 min on a 2.5 gallon shower head. That only works out to 25 gallons.

The product looks like the retail version, so I'm not sure how it would be stripped down. It monitors hot water use and controls when the heater is activated, which is all the features of the retail unit.

I'm going to want access to data, if not my personal usage statistics, then the program as a whole to see how much energy is being shifted or saved. I'd be very surprised if it had a positive return on investment. More likely is they take our utility money, and "save" some fraction of it; wasting the rest.

[samwichse]

My utility has these on most people's heaters. It doesn't save you anything, it just lets them shut off your heater when loads are high (typically 5:30-7:30 pm) or there's a large energy hog event (super hot day with everyone's AC running, super cold day when everyone's on emergency heat).

So it's not for energy savings, it's for "grid health" so they don't have to switch on expensive peaking plants.

My provider gives you a one-time $50 bill credit if you let them install it. I declined to participate since I have a hybrid hot water heater anyway. That saves me about $20-25/month and doesn't use the 4.5kw heating coils regular units do that make them such a potent drain on the grid.

[ksa8907]

I was able to find what the typical cost is per kwh to build new generation capacity. Cheapest option was advanced combustion turbine plant at roughly $700/kwh.

That makes $150/ 4kwh water heater "generation" very cheap.

[redpoint5]

Well shoot, they should be paying me to put the thing in then.

If the cheapest option is $700 per kWh, then supplemental power from battery storage might be economically viable now. Tesla claims a cost of $190 per kWh of battery capacity. You could get 3.5 hours of battery runtime for that $700.

[ksa8907]

Originally Posted by redpoint5

Well shoot, they should be paying me to put the thing in then.

If the cheapest option is $700 per kWh, then supplemental power from battery storage might be economically viable now. Tesla claims a cost of $190 per kWh of battery capacity. You could get 3.5 hours of battery runtime for that $700.

Grid scale battery storage is starting to gain traction, still some fear around longevity and maintenance costs though.