Mar 19·edited Mar 19

I'm becoming more and more aware that it is all about the peak hours for utilities. This was driven home for me recently when I became aware of a new pilot rate structure introduced by my utility Public Service of New Mexico (PNM), https://www.pnm.com/timeofday .

Summer : 5 - 8 pm = $0.31 / kWh. Off peak = $0.08 / kWh.

Winter : 5 - 8 am & pm = $0.17 / kWh. Off peak = $0.07 / kWh.

It doesn't take a rocket scientist to see how short-duration energy storage, e.g., batteries, can be part of the solution to this problem.

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Even the EIA source data is not clear about kWh units. A kWh(thermal) is a unit of heat energy, and a kWh(electric) a unit of electric or work energy. It takes roughly 3 kWh(t) to generate 1 kWh(e). The comparisons of space heating and space cooling are devoid of meaning without more information.. Typically heating is with kWh(t) from natural gas burning, and cooling with kWh(e).

Note China is using rejected heat from nuclear power generation for district heating. A review of my new book, New Nuclear is HOT, has an example of this. https://energycentral.com/c/ec/book-nuclear-hot-glowing-steel-public-support

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Energy is energy. The reverse is also true with heat pumps, i.e., 1 kWh(e) = 3 kWh(t).

Also, the 3 to 1 thermal to electric is no longer representative with CCGT reaching efficiencies of 60%.

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Makes me ponder if it wouldn't make sense to actually over heat the house or at least stop letting it cool down while away at work in the winter so that there isn't such a spike in demand late in the afternoon. We want it to cool again a little before going to sleep so you might not need to run it much at peak time.

Getting a heat pump but since I didn't previousely have A/C and we currently heat with natural gas we won't be reducing demand on the grid. In the summer it may also be a benifit to keep the house a little cooler while demand is lower. I don't think the current demand charges are a big enough difference to stress about it too much yet.

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That makes sense. Use the house itself for energy storage.

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Heat storage will be big in a decarbonized future

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Peak heating (especially in temperate climates) is the main show for ‘electrifying everything’.

It’s also a demand that will not be particularly responsive to price signals so firm power will be crucial, as will anything to limit the actual demand.

GSHP >> ASHP. District heating even better.

This is also a key reason we need a bunch of nuclear - the coldest days often coincide with very low wind output, and it’s the wrong season for solar to help much.

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One way to save energy as more households move to heat pumps would be two zone climate control. People usually want to sleep in a cooler room and be active in a warmer room. Heat pumps can be amazingly efficient maintaining room temperature, but warming or cooling the house takes a lot of energy because everything in the house gets cold or warm. Right now, most thermostats are whole house thermostats. You can't keep the bedrooms at one temperature and the living areas at another though that would be more efficient.

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Air conditioning is such a contributing factor. I’m keen to see more technology advances for residential cooling systems!

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I was an airbnb host and had AC until a family from Russia stayed at my place and turned the AC so low they turned the heat back on, lived like that for a month, and checked out. The systems were running like that for a week afterward. No More AC For Anyone after that. [Personally, I only use AC when we’ve had four consecutive days of 36º or higher with 80% humidity. I use it at most twice a year, and only for two or three days.] If I need the cool to fall asleep, I go downstairs. People in temperate climates use AC simply because it’s a luxury habit, and it’s culturally trained out of us (if you weren’t raised with AC, you know better how to deal; if AC is taken for granted, they object if you turn it off and open a window!). We should be building better than that, and also questioning these luxury habits (for when it’s not out of sheer necessity). Of course, glass condo towers absolutely require AC, they couldn’t exist without AC. We should be building better than that. And if you have a basement—and a lot of building codes don’t enforce that you do (where conditions permit it; whereas in Florida they don’t)—families and buildings would have a source of thermal mass coolness. We should be maximizing that kind of access already by making subterranean space attractive, useable, and functional for these purposes. Plus, if geothermal systems can provide heat, they can also provide cool.

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Must be another Canadian. Me and my wife both grew up without A/C then bought a house with A/C. It worked for one or two summers and we've carried on without it for 14 years. I have often said that it's only a few weeks a year we would need it and living in the heat helps aclimate anyway. We are motivated by the rebates to get a heat pump so we can cool or more importantly control the humidity in the house in the summer. We might be getting soft or maybe we really will only use it a few weeks a year.

My wife's 80 year old mom has lived without it her whole life but I worry about her needing it more than me for now.

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Nighttime charging may not be best for EVs, depending on the generation mix. In a place with lots of solar generation, for example, afternoon charging is better. The best way to identify the best timing and coordinate demand and supply is through local energy markets using transactive platforms, in which the devices (thermostats, EVs, solar PV) submit purchase bids and sale offers and the market price that emerges is used as the autonomous control signal for the devices. That way, in the afternoon when the solar is in high supply it will drive down the price, and as the market price hits the various EV purchase bids, they purchase and charge. This coordinated PV/EV charging makes the best use of the available solar generation.

Another important factor in building consumption is the thermal mass of the building. Insulation increases the thermal mass and reduces the energy required for both heating and cooling. It also makes it a lot easier to move supply and demand, by making it more convenient for the building occupants to be more flexible.

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An energy market only optimizes if all energy is bought and sold at the spot price, but that requirement makes it impossible for people to plan their energy use. You could let consumers hedge with options or warrants as they can for stocks, but then you lose market efficiency.

Most people are going to want to know what things will cost a few days in advance. Meanwhile, weather, collective demand, equipment status and so on are hard to predict. Having unpredictable prices is not the way to make consumers happy. Look at the typical reqaction to surge pricing, hidden fees and so on.

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This is a very useful post for innovators in sustainability. There is a huge opportunity to figure out how to match supply and demand for electricity now and as everything becomes electrified. I'm working on a system that does this. Net-zero itself is not useful if timing is mismatched. We need to minimize imported grid power at our homes and buildings. Thank you for this Hannah!

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To Robert Hargraves:

Sir -- you are correct in your figures -- using the power generating "stuff" we presently are using.

But we don't need it - because there is - and has been, for over a century now:

--- an "electronic way" to produce the electricity needed here in the US - and around the world.

And guess what - all you US electric bill payers and "fossil-fuel for your vehicle purchases:

the US Federal Government / Universities / and Commercial sectors contacted - have all taken a "not interested " / not invented here / no funding or technical aid will be made available to the following electric power supply -- because it wasn't "commercialized":


--- laboratory tested and proven / continuous 120 VAC / 60 Hz electric output power while powering an AC motor:

--- at 293% "over-unity"

--- on Sept. 10th. 1984.

--- US patented - see US 5,146,395 / A POWER SUPPLY INCLUDING TWO TANK CIRCUITS / with "regenerative feedback" / Nikola Tesla based / solid-state electric power supply -- with the ABSTRACT verifying continuous "electronically produced / "over-unity" electric power output / granted:

--- on Sept 8th. 1992.

The power supply now has "selectable" VDC electric output power levels of the following:

--- 24 VDC; 48 VDC: 72 VDC; 120 VDC; 240 VDC; 260 VDC; 380 VDC (to be added), 400 VDC; and 480 VDC.

Specific VDC output power levels can be DC/AC inverted to the following output power levels:

--- 120 VAC; 240 VAC; 260 VAC; 380 VAC; 400 VAC; and 480 VAC, with;

--- 3-phase / 400 VDC / 160 Amps per phase (480 Amps) for vehicle power -- "... if it's good enough for TESLA.....".

Each VAC output power level will have the following:

--- the correct number of output phases / output voltage level / output frequency / and output amperage level.

The maximum continuous / "over-unity / output power level is:

--- 480 VDC or VAC / 480 Amps which equals:

--- 230,400 Watts; 230.4 kW ; or .2304 MW -- however you care to describe it.

All output power voltage levels were produced from an "on-board" power source of 15 Watts @ 12VDC, and:

--- all output voltage levels are produced without using any voltage transformers.

All of the above uses "resonance":

--- discovered and patented by Nikola Tesla / US 511,916 / Jan. 2nd. 1894.

The power supply can be installed either:

a.) "at" any existing or new "stationary" location, i.e., at any home; apartment; office-space; commercial or industrial-site -- world-wide, or;

b.) "in" any existing or new "movable" vehicle of any size, shape, or weight - that is battery or internal combustion engine (of any kind or type) powered - by retrofitting - repowering each vehicle with either:

--- direct electric power of any quantity or voltage, or;

--- electric powered AC motor(s) as required -- be the vehicle on land / in or on the seas / or in the air as a propeller; rotor; turbine; or hi-bypass jet powered private or commercial aircraft -- making available the following:

b1.) unlimited range of travel and / or movement, and;

b2.) unlimited time of travel and / or movement.

It makes everything we presently use around the world - to produce our electricity and power our vehicles:

--- totally redundant and unnecessary.

And the truth of the situation is:

--- we have had the information to produce all of the "electronically produced"; i.e., "environmentally clean" electricity; - the world would ever need:

--- for over 134 years -- because Nikola Tesla discovered / invented / and patented all of the required information to accomplish it:

--- between the years 1890 and 1894.

It's all there.

We just didn't look for it: -- because the science of Classic Physics had been dictated for Lord only knows how long:

--- that "over-unity anything" - was totally impossible:

--- until they "finally" accomplished it, i.e., "over-unity power production - producing incredibly high heat temperatures;

--- announced on Dec. 13th. 2022 and again on Aug. 8th. 2023.

They "changes the rules that they had written -- because "they" did it.

Also - it must be stressed: that Commercial interests did not want a power supply available that would replace and make redundant:

--- all of the money making electric generators and power grids they had already built and planned to build:

--- and that continues today.

It is because of that condition - that we now have the Global Warming / Climate Change disaster we created:

--- staring us in the face.

The world is not going to be able to produce enough generators / wind / solar / what-ever electric power sources to fill the world's needs are now being found out:

--- because we will never be able to build enough power grid capacity to carry the electricity from point A to point B -- in the time required - to save the planet from blowing past the tipping point of no return.

The US is "way behind the eight-ball" on this - and there is 5 year backlog - due to bureaucratic holdups - which they will never fix.

The power supply that could accomplish what is required:

--- is totally solid-state electronics / requires zero "fuel" of any kind or type / at any time.

--- is environmentally clean - in that it emits nothing.

--- is small - 2.5 cu. ft. / lightweight - 30 lb. / and inexpensive to produce - under $2000 per unit.

--- has it's own on-board "start-up" power source / eliminating both "recharging" or external power source connections;

--- can have multiple units connected together for higher output levels - "just like batteries".

This makes it the only power supply in existence that can be used to retrofit - repower each and every existing "heat-sourced (including Atomic) and water pressure dam site located high voltage electric power plants, by:

--- placing multiples of "rack-mounted" power units against the interior walls of each site's Turbine Halls (where the generators are locate);

--- connecting the new / "Green-Clean" / matching electric power output through each site's control room(s) to the site's existing connected intertie / power grid(s);

--- allowing for shutting down "only the polluting 'power-source(s) and revolving generators", while;

--- continue to maintain a 24 / 7 - 365 days a year "base-load" output from each plant site, while;

--- saving all , plus the "effected jobs" - through retraining.

Got a challenge for you Ms. Ritchie.

You're real good at digging out statistics and publishing them.

What would it take for you:

--- to take the electric power information above - using the proper amount of required electric power:

--- per hour / per major electric power system used around the world (of which there are about 1 /2 dozen, give or take a few; -- and compute / calculate:

--- how many of these power units could do the job of cleanly powering the world:

--- in time to save us from burning up this rock that we all live on?

And this challenge is is from a full-blooded Scotsman - whose ancestry has been positively traced, on my grandmother's side - back to Rob Roy McGregor: -- so I'm not fooling:

--- I would like to know how many power supplies have to be manufacture and installed in time: because:

--- I have been invited to take the technology to a free-world country outside of the US - for funding / manufacturing and installation:

--- there first, and also around the world at the same time.

You see - Mr. Hargrave: we don't need 3 kWh(t) to "generate" 1kWh(e).

We only need 2 (on-board) 9VDC rechargeable batteries per standard unit:

--- - to "kick-start" the power supply electric circuitry;

--- which incidentally the world has been using - since the year 1900:

--- as part of the "radio station to radio station - tuning circuitry :

--- in every AM or FM radio manufactured:

--- since Tesla invented and submitted his patent application -- so don't try and tell me it doesn't / can't work - because of stuff like:

--- "Conservation of Energy (which doesn't exist as an entity) Theory;

--- "2nd Law of Thermodynamics (which mainly deals with steam engines):

--- Perpetual Motion -- look up the definition: you'll find that "perpetual motion" can't have any input while the power supply does: every high frequency cycle;

The power supply is called the "POD MOD" - standing for "P"ower "O"n "D"emand "MOD"ule.

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"Most people heat their homes in the morning before work or school, and in the evening when they get home."

Maybe if the home - typically a house - is poorly insulated and has low thermal mass. That needs to change. Heat pumps should be able to heat the house when electricity is cheap (and green), over 4 to 8 hours per day.

We went for "Solar Hot Water with heating support" in the south of Germany. These want a big heat store - as big as fits through the doors. In our case, that was only 750 litres, which I reckon stores almost 1KWh per 1C temperature differential. A heat pump could heat the water to 50C and allow it drop to 30C, giving a store of 20KWh. Add in the thermal mass of the building - is that enough?

A poorly insulated (ie typical British) house might need 100KWh in a day.

That might be heatable in two four hour slots per day, ie 2am to 6am and 12 noon to 4pm. Octopus energy has a tariff for this.

But a problem in the UK is that most homes don't have space for a thermal store - ie a 1000 litre water tank. Though I think on current trends LFP batteries might soon be cheap enough to charge up at night and heat the home via a heat pump in the evening.

But that still doesn't help with the general winter demand in northern places like the UK. If all heating is electric, then demand in the winter could be 2.5 times higher than on a pleasant (20C) summer day, just when the solar power is delivering next to nothing.

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In Europe, France is perhaps quite similar, except without the need for air-conditioning. Decades of cheap nuclear power, and a limited gas distribution network, means lots of resistance heating, often as storage heaters.

I recall even in 2014, even in a ski resort, staying in a brand new apartment, just opened, heated by electric radiators all over. As soon as I arrived, I was thinking "why no ground source heat pump?". The first morning, about 8am, the electricity supply died. At lunch time EDF were digging through the snow to get to the burnt out cable.

If France could replace a lot of the electric heating with heat pumps, they could probably free up 5 to 10 GW of clean electricity that could replace German coal.

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How does household demand compare to commercial and industrial demand? For the purposes of grid planning, what is the value of only considering household use?

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Thank you - interesting to see these overall figures - and to compare my own household usage where cooling is electric and heating gas.

btw - there is a typo in "... demand that’s important, but it’s timing...." s/be "....demand that’s important, but its timing."

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The heating problem is an issue with cold spells and air source heat pumps in the South East US. Average winter night time temperature is in the 40s F which heat pumps work great at, but we’ll have cold spells down into the 10s or single digits. The air source heat pumps, having less capacity at lower temperatures, add emergency resistive heat to keep up. This overloads the electrical grid and has caused rolling blackouts. Lately it seems the solution is for the utilities to add more gas peaker plants which is not ideal.

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