Featured The impact on utility rates in CA of EV charging

I'm not austingreen...but

My utility (PG&E) upgraded to smart meters about 10 years ago
There are non-mandatory optional rate plans that include TOU metering.
They allow you to switch and for the first year or two (?) they compare your bill each month to the old and new accounting to show you the difference and allow you to switch back if you lost out

Mike

 

Industrial and many commercial customers have been paying max usage charges since forever, but they seem to be appearing in more residential areas too. This does make sense for grid stability during high demand periods.

I hope you have, or can, change any traditional electric resistance water heater to a heat pump model. These save considerable energy, especially in warmer climates, and also reduce peak demand. These should work for most electric water heat customers, though there are still some locations and niche needs where these don't work well.

And one may even be able to program them (at least some models) around time-of-use energy rates, setting the thermostat higher during off-peak times to store some extra water heat, then lowering it during on-peak to delay most of the recovery to the next off-peak period. But I don't know if or how well these can play with demand controllers.

Heat pump clothes driers are becoming a thing too, also saving energy. But this market isn't yet mature, so many people may not find the current product selection acceptable. These units also take longer to finish the job than do traditional models, though the ventless feature will appeal in some places.

 

Smart meters allow the utility to better plan and schedule their power plants. They let them know that voltage is fluctuating before power goes out, so they can prevent blackouts.

The only concern about a smart meter versus your old meter is security, as the utility will have more granular information about your energy usage and they like everyone else can be hacked. Still I don't really care if people know when I use power.

My utility has smart metering but does not have time of use metering. It is simply because the stress to the system is mainly industrial and air conditioning, and it would only help here on very hot or cold days. They do subsidize smart thermostats that they can reduce hvac power when the grid needs it. I have one and they have only reduced my air conditioning once in the 6.5 years I have had it. They may implement time of use when more plug-in vehicles go on the grid, or they may just throttle them down, as they subsidize chargers that they can turn down too. The grid operator asked those of us with EVs to not charge for a couple of days last spring, and asked us to set our air conditioning to 78. I charged my car to 100 before the suspected shortfall, but I wasn't going to make my house that warm, I have solar and should be able to use it on hot days ;-)

In california with the energy shortfall time of day makes sense, I don't know if it does in your area.

 

Thank you guys for answering my questions.

Appreciated the comment about the heat pump clothes dryers. I didn't know these existed but after reading the post about them, I went to our local Lowes website and they actually have some for sale.

We have a heat pump water heater and it saves bundles of money - I am certainly going to investigate the heat pump clothes dryers as they will save an equal amount of money if not more than the heat pump water heater. Our electric utility gave us quite a rebate when we bought a heat pump water heater - I am going to see if they have a similar program for the heat pump clothes dryer.

Our current dryer has a 240 v 24 amp electric draw
The LG Heat Pump Dryer has a 120 v 3.1 amp electric draw
The Heat Pump Dryer also is ventless so it is not taking heated or cooled conditioned home air and exhausting great amounts of it to the outdoors.
These seem like outstanding energy saving products.

 

Use an exhaust duct to vent the HPWH's cold exhaust air outdoors, outside the crawl space. This will prevent it from chilling the floor. You can also use an intake vent, if desired. Many or most HPWH models should take ducting, though make sure this is part of the selection criteria.

My crawl space isn't tall enough for standard height water heater tanks, and I haven't seen any short squat HPWH models. My original water heater was in a closet in the kitchen. After a leak led to floor damage, and we replaced that with hardwood flooring, I decided to avoid a future repeat by having the hot water system re-plumbed to the garage, which is an ideal location for HPWHs. The old water heater closet was reconfigured as an enlarged pantry, which greatly pleased the spouse.

I suggest re-checking that. My HPWH saves considerably more energy than my old fashioned electric clothes dryer uses in total. Though these figures will vary by household size and habits and climates.

I'll try to dig up some actual figures this afternoon. My water heater has a hardwired energy meter (a refurbished traditional utility meter), and I had the dryer on a similar meter (wired into an extension cord) for several years to characterize its energy use.

That ventless feature, not exhausting previously conditioned air, is potentially a big energy saver in itself, apart from the savings of the appliance itself. But the amount will vary considerably by climate zone.

The longer cycle times might potentially not play well other with some other household members not as committed to energy savings. And I believe this market of heat pump clothes dryers is still fairly immature, like HPWHs were a decade ago. But I have no regret jumping to a HPWH back then.

 

It might even be possible to duct the water heater's cold output through a floor vent during the summer.

 

On the Heat Pump Dryer, I realize the electric savings would be comparable to the Heat Pump Water Heater - I was also considering the conditioned air being exhausted outside the home with a regular dryer - for example today it is 25 degrees outside and we will run our dryer for probably 45 minutes taking conditioned air from the home and exhausting it outside - with this exhausted air being replaced by 25 degree from outside that has to be heated. In the summer we would be exhausting cooled air to the outside for 45 minutes and replacing it with air that is over 100 degrees that has to be cooled.

Our Heat Pump Water Heater is in the basement where it dehumidifies and cools the air. There is no exchange of air from the outside. Ground heat migration from the 8 foot concrete walls in the basement keeps the basement at a constant temperature year around.

 

In AC-dominated climates, that "waste" cold air is quite valuable to offset other AC, effectively increasing overall dwelling energy efficiency.

If one can put a diverter into the exhaust duct, to direct it to someplace useful in the summer and outside in winter, then please do so. I'm in a milder climate with little need for AC, but did put in a diverter to slightly chill the garage in summer. Send it all outside the rest of the year.

... that reminds me , I forget to switch my diverter this fall. With freezing temperatures and a few falling snowflakes today, I need to go flip and cap it right now! The garage is already cold enough without the additional chilling.

 

We went with a stackable Whirlpool washer and heat pump dryer. No vent, it provides heat in the winter and does not overheat in the summer. Cheap to operate without sucking inside air, heating, and exhausting outside:



Bob Wilson

 

How much does it heat the room - is it uncomfortable or just noticeable?

Was the savings on your electric bill noticeable?

Are you guys satisfied with its performance?

Sorry for all the questions I think this is a fascinating product with a large energy saving capability.

What a great way to use a heat pump application!

 

Our original GE washer and dryer had given up the ghost nearly 10 years earlier so I don’t have anything to compare.

It does warm but only a couple of degrees. It runs on a regular 120 VAC circuit along with the front loading washer. It has a water drain shared with the washer.

The heat pump removes the water from the air the clothes tumble in. Dry air removes water from the damp clothes. The front loader spins the heck so the clothes come out damp.

Bob Wilson

 

Sounds like the cold loop of the heat pump is used to remove the moisture from the exhaust. No damp air. If there isn't a drain, the water collects in a tank, like a dehumidifier.

 

Where does the water from a ventless heat pump dryer go? Down the drain! Either the same drain as the adjacent washer, or down whatever drain that you chose to pour out the collection tank.

According to GE Appliances:

Any exhaust air shouldn't be hot and humid. It should be slightly warm, and dry or dehumidified. Though if the machine's air path is fully closed, it just won't have any exhaust air.

The heat will be far less than a normal electric dryer. It should have no heating element, just the waste heat given off by the drive motor, fan, and refrigeration compressor. While it also has both a heat pump / refrigeration condenser and evaporator, the heat and cold from each should balance out to zero (or to the amount of electricity put into the compressor).

If the dryer's air path is partially open, it should de-humidify the laundry closet, making the hanging clothes dry faster. Though if the internal air path is fully closed, then it won't succeed in room de-humidification.

Kill those web trackers. You can learn about those rebates from here, from general home energy conservation advice, and from the utility's own advertisements and billing inserts.

 

Kalispell low temperature supposed to be -21f this wednesday.
Wonder how that affects a Dryer's capability if it's 33°f in the garage .... near or below freezing

 

Hang the clothes to freeze dry.

 

I wonder if such laundry placement requires electric heat tape on the washer's water lines.

Be sure to hang it in the sun, so the ice sublimates much faster.

 

I was tardy in digging up those figures, but have them now.

The old electric water heater was metered for just 32 days before the meter was temporarily moved to commission my rooftop PV system, and the old water heater replaced by a heat pump model. In that 32 days, it burned 280 kWh, or 8.75 kWh/day, or 3194/year. Making allowance for vacations and other absences, I'll guesstimate closer to 2800/year.

Since then, the heat pump water heater (AirTap AirGenerate, Tier 2 (the highest then available), northern climate energy factor 2.0), has burned 10406 kWh in 3489 days, or 2.98 kWh/day, or 1089 kWh/year. That means it saves somewhere between 2100 (a stretch) to 1700 (more realistic) kWh/year. The savings is better than its Northern Climate Energy Factor predicts, suggesting that my mild local climate is not as cold as the (now obsolete) Northern Climate scale's weighted average.

The newest Tier 4 models have Uniform Energy Factor ratings (not identical to the old Northern Climate scale) of 3.50 to 4.0, saving considerably more than mine, though likely just half the total energy use. Compared to my current 1089 kWh/year, these new models could be expected to use about 700-800/year??

Now my traditional electric clothes dryer. It was metered just over 6 years, using 3019 kWh in 2199 days, or 501 kWh/year, varying some by how diligent we were in using an outdoor clothesline in summer (not very). That is far less total energy than the heat pump water heater saves. And the potential direct savings of a heat pump clothes dryer is, what, about half??

That vented clothes dryer energy does need adjustment for the conditioned air that it exhausts, but I have no good gauge for that. My ductless heat pump, which provided the bulk (80% ??) of space heat before this year, averaged 1360 kWh/year over nine years of metering. (The direct electric heat at the other end of the house is not separately metered.) I'll make a wild swag that the dryer venting consumed 250 kWh of that, for a total dryer energy cost of 750 kWh/year. So maybe a ventless heat pump dryer might save me 2/3rds of that, or 500 kWh/year?

I now have a second ductless heat pump at the other end of the house, on the same meter as the original, and entirely displacing the old electric heat. It will give me a more accurate space heating energy cost, but I won't have a full year's energy record on it until the end of this heating season.