Low cost off peak electricity

hot_rod

A power utility in New England is involved in a pilot project to sell at real-time cost.
The can send a signal out every four seconds to rate users. An energy company is building a control to take that signal and start a buffer tank charging.
The power company claims their rate can go below 1 cent at times.
A friend is designing 4- 119 gallon electric tanks that would charge at some low rate condition.

Jamie Hall

So it can. The downside, of course, is it can also go up... a long ways. Great if all your heavy loads can be intermittent. Otherwise, maybe not so much.

hot_rod

I think you mentioned paying 31 cents a kWh. Does it go beyond that ever?
Certainly you would take 20, 10, or even 1 cent per kWh whenever it was available.

I think it is a step in the right direction for a utility to offer lower consumer cost instead of a fixed rate.
Seems a win for the consumer. And there must be a win for the utility to manage their grid?

JDHW

I think time of day tariffs are coming for all of us and does make some sense in terms of making more efficient use of generation and transmission assets. There is a UK company (Octopus Energy) that are offering some interesting tariffs based on the time of day.

Their more flexible one is rates for import and export of energy based on 1/2 hour time slots (this is the way the national wholesale pricing system works). They provide information from a website for the tariffs every day in advance. At the moment price of electricity is around £0.28 per kwh for a fixed rate and the flexible tariff can be much lower and is capped at £1.00 per kwh. If the nation price goes negative, which it does occasionally, they pay you!

This company also offers a three part tariff for import. A base rate for most of the time then two cheaper 3 hour slots (one in the night and one mid afternoon) to heat your house up with the heat pump and then a peak rate late afternoon/early evening.

Interesting times ahead with more heat pumps/electric cars and no obvious viable plans to scale generation and transmission.

John

Hot_water_fan

Seems like a great idea, incentivize people to respond to grid conditions. My utility does a demand response program for the summer peaks, seems to work great. 

Hydronics is so well suited to energy storage and demand response! 

hot_rod

This SunAmp product could have some interesting applications. Steam applications?
The case studies tell more of the story 

Jamie Hall

There are certainly many uses where time of day or off peak pricing can be very valuable -- heating, as more people convert (willingly or unwillingly!) is an excellent example, and will be helped along by designs which provide for significant buffering, so that it is possible to meet short term demands at peak hours without having to use peak hour electricity.

In fact, there are a lot of ways this type of approach can help -- for one thing, it has the potential to reduce peak electricity costs, as there will be less need to fire up expensive peaking power plants to keep the lights on.

A lot of opportunity there for creative and practical thinking. One hopes that some creative and practical thinking will turn up in the regulatory and legislative entities which mandate all this...

And for @hot_rod , Connecticut does not offer peak or reduced hour rates to residential properties, although some industries have them. That $0.31 is the current residential rate, but the anticipation is that it will rise by about 5 to 10 percent per year for the foreseeable future.

Hot_water_fan

SunAmp and other phase change batteries could be impactful. I love the idea of storing heat at exactly the temperature I need, no more no less. If it gets enough cycles, I could see a thermal battery coming in cheaper than propane or oil as a low temp backup or peak shaving concept, and it if can be used as daily or more arbitrage, the savings could really stack up. That’s one thing I dislike about TOU rates, you usually only get one or two low periods per day, but if you have more real time pricing you might bank more savings per day. 

Could also be effective for wood boilers, let you fire most efficiently using much less space for storage. 

@Jamie Hall  $.31/kWh! I feel for you! The land of pleasant living is less than half that and the 3rd party energy providers can bring it even lower because they have lots of intro teaser rates. 

Dave Carpentier

Ontario currently (pun ?) lets us pick either TOU or Tiered pricing.
In TOU, 7pm-7am is the super cheap slot, 11am-5pm is the very expensive slot.
In Tiered, its a bit of a cheaper rate for the first 800 kwh or so, then it goes up.

We did the TOU for years but then switched back to Tiered during a period when 2 of us were at home all day. Might go back to TOU again, it wasnt too hard to wait until 7pm to do laundry etc.

I think the problem with live pricing is the huge peaks in pricing you may have to absorb. At least with TOU on a set schedule, you can plan your day.

ChrisJ

How do these "tanks" work?

GroundUp

I was offered a $.03/kwh rate for dual fuel heating (LP backup) at a rental property I own. I'm still debating whether or not to go that route, as I would need a larger electrical service installed to heat the space adequately on a design day. Regular rate is $.08

The Steam Whisperer

We've had that type of system for some time in Chicago...probably because the systems were developed at IIT in Chicago. Even residential customers can sign up to have dishwashers, cooling and other appliances put under control of the utility for better rates in exchange.
I haven't signed up for it myself since our yearly electric bill, including summer cooling, is only about $700 to $800 per year.

Hot_water_fan

I was offered a $.03/kwh rate for dual fuel heating (LP backup) at a rental property I own. I'm still debating whether or not to go that route, as I would need a larger electrical service installed to heat the space adequately on a design day. Regular rate is $.08

@GroundUp that’s surprising, you can’t just use the LP in lieu of a service upgrade? 

jumper

GroundUp said:

I was offered a $.03/kwh rate for dual fuel heating (LP backup) at a rental property I own. I'm still debating whether or not to go that route, as I would need a larger electrical service installed to heat the space adequately on a design day. Regular rate is $.08

Those rates will increase drastically.

GroundUp

Hot_water_fan said:

I was offered a $.03/kwh rate for dual fuel heating (LP backup) at a rental property I own. I'm still debating whether or not to go that route, as I would need a larger electrical service installed to heat the space adequately on a design day. Regular rate is $.08

@GroundUp that’s surprising, you can’t just use the LP in lieu of a service upgrade? 

How does that take advantage of 3 cent power? The current boiler is LP, and I'm debating making the primary heat source electric while keeping the LP as backup due to the rate which is less than half of what LP costs. I can't cover the full heating load without upgrading service.

GroundUp

jumper said:

GroundUp said:

I was offered a $.03/kwh rate for dual fuel heating (LP backup) at a rental property I own. I'm still debating whether or not to go that route, as I would need a larger electrical service installed to heat the space adequately on a design day. Regular rate is $.08

Those rates will increase drastically.

Considering that's the lowest it's ever been, and this is a new program, I'm not concerned about it.

hot_rod

Electric boilers are not all that expensive, easy to pipe in. I'd certainly take that 3 cent gamble.
Certainly we have all seen LP prices skyrocket in recent years.

LP would need to be under about .70 per gallon to compete with that 3 cent power

Hot_water_fan

How does that take advantage of 3 cent power? The current boiler is LP, and I'm debating making the primary heat source electric while keeping the LP as backup due to the rate which is less than half of what LP costs. I can't cover the full heating load without upgrading service.

You misunderstood me - my apologies for not explaining better. Why not size the electric boiler to the largest size it can be before needing a service upgrade. Then use the LP from there. So if you need 20kw but can only fit 15, install the 15k and the last 25% will be a combination of LP + electric. 

Hot_water_fan

Those rates will increase drastically.

@jumper why? $.03/kWh is around average annual wholesale price, so if they’re using LP for the peaks, then I wouldn’t be surprised if the utility is making plenty at $.03/kWh and avoiding the highest marginal cost hours. The utility has to love adding a bunch of easy kwhs - helps them spread out costs. 

ChrisJ

@hot_rod

What are the tanks you mentioned?  Do they store hot water?  Or is it some new setup?

hot_rod

ChrisJ said:

@hot_rod

What are the tanks you mentioned?  Do they store hot water?  Or is it some new setup?

The SunAmp look to be a thermal battery, phase change concept

https://sunamp.com/

hot_rod

Dave Carpentier said:

Ontario currently (pun ?) lets us pick either TOU or Tiered pricing.
In TOU, 7pm-7am is the super cheap slot, 11am-5pm is the very expensive slot.
In Tiered, its a bit of a cheaper rate for the first 800 kwh or so, then it goes up.

We did the TOU for years but then switched back to Tiered during a period when 2 of us were at home all day. Might go back to TOU again, it wasnt too hard to wait until 7pm to do laundry etc.

I think the problem with live pricing is the huge peaks in pricing you may have to absorb. At least with TOU on a set schedule, you can plan your day.

Yes it will depend on each individual application. If you had a high mass shop slab, you might load it up during the lowest $ period, and coast off it during high peak. If my shop went off my T stat by 3-5 degrees, I could deal with that I& it were 3 vs 30 cent electricity options🤓
Or 1000 gallons of thermal storage for example. So system type and owners comfort level will be part of the choices.

My previous shop had 500 gallons of thermal storage. A $300 used LP tank with some fiberglass and bubble wrap insulation. Cheap and effective, endless DHW with that much stored energy.

ChrisJ

The Steam Whisperer said:

We've had that type of system for some time in Chicago...probably because the systems were developed at IIT in Chicago. Even residential customers can sign up to have dishwashers, cooling and other appliances put under control of the utility for better rates in exchange.
I haven't signed up for it myself since our yearly electric bill, including summer cooling, is only about $700 to $800 per year.

Dave please check your PM's when you get a chance.

GroundUp

Hot_water_fan said:

How does that take advantage of 3 cent power? The current boiler is LP, and I'm debating making the primary heat source electric while keeping the LP as backup due to the rate which is less than half of what LP costs. I can't cover the full heating load without upgrading service.

You misunderstood me - my apologies for not explaining better. Why not size the electric boiler to the largest size it can be before needing a service upgrade. Then use the LP from there. So if you need 20kw but can only fit 15, install the 15k and the last 25% will be a combination of LP + electric. 

Ah, pardon me. I have considered that option as well, but have not delved deeply enough into that yet to come up with a proper control solution. I believe I have a way that would work, but have not yet confirmed that.