HEAT PUMPS REDUCE VERY LITTLE CO2 IN MY VERMONT HOUSE, AS THEY DO IN ALMOST ALL NEW ENGLAND HOUSES

I installed three heat pumps by Mitsubishi, rated 24,000 Btu/h at 47F, Model MXZ-2C24NAHZ2, each with 2 heads, each with remote control; 2 in the living room, 1 in the kitchen, and 1 in each of 3 bedrooms.

The HPs have DC variable-speed, motor-driven compressors and fans, which improves the efficiency of low-temperature operation.

The HPs last about 15 years. Turnkey capital cost was $24,000. GMP, the electric utility, provided a $2,400 subsidy.

http://www.windtaskforce.org/profiles/blogs/vermont-co2-reduction-o...

 

My Well-Sealed, Well-Insulated House

 

The HPs are used for heating and cooling my 35-y-old, 3,600 sq ft, well-sealed/well-insulated house, except the basement, which has a near-steady temperature throughout the year, because it has 2” of blueboard, R-10, on the outside of the concrete foundation and under the basement slab, which has saved me many thousands of space heating dollars over the 35 years.

 

I do not operate my HPs at 15F or below, because HPs would become increasingly less efficient with decreasing temperatures.

The HP operating cost per hour would become greater than of my efficient propane furnace. See table 3

NOTE: On 22 Jan., 2022, the temperature was -20F at my house. As a test, I operated kitchen heat pump, one of my 3 heat pumps.

After about 15 minutes, there was plenty of lukewarm air coming from the wall-mounted condenser unit, but it was much less warm, than at 15F. That lukewarm air would not have heated my kitchen.

My conclusion: The name cold-climate heat pumps is merely an advertising gimmick. It has no basis in the real-world. If you have a wood stove or pellet stove, by all means use it, because it is the the lowest-cost way to space heat a house, even an energy-hog house

High Electricity Prices

 

Vermont forcing, with subsidies and/or GWSA mandates, the build-outs of expensive RE electricity systems, such as wind, solar, batteries, etc., would be counter-productive, because it would:

 

1) Increase already-high electric rates and

2) Worsen the already-poor economics of HPs (and of EVs)!!

https://www.windtaskforce.org/profiles/blogs/high-costs-of-wind-sol...

 

PART 1

 

Energy Cost Reduction Due to HPs is Minimal

 

- HP electricity consumption was from my electric bills

- Vermont electricity prices, including taxes, fees and surcharges, are about 20 c/kWh.

- My HPs provide space heat to 2,300 sq ft, about the same area as an average Vermont house

- Two small propane heaters (electricity not required) provide space heat to my 1,300 sq ft basement

- I operate my HPs at temperatures of 15F and greater; less $/h than propane

- I operate my traditional propane system at temperatures of 15F and less; less $/h than HP

 

- My average HP coefficient of performance, COP, was 2.64

- My HPs required 2,489 kWh to replace 35% of my fuel.

- My HPs would require 8,997 kWh, to replace 100% of my fuel.

 

- The average Vermont house COP is about 3.34

- The average Vermont house requires 2,085 kWh to replace 27.6% of its fuel, per VT-DPS/CADMUS survey. See URL

 

https://afdc.energy.gov/files/u/publication/fuel_comparison_chart.pdf

https://www.nature.com/articles/s41597-019-0199-y

https://acrpc.org/wp-content/uploads/2021/04/HeatPumps-ACRPC-5_20.pdf

 

Before HPs: I used 100 gal for domestic hot water + 250 gal for 2 stoves in basement + 850 gal for Viessmann furnace, for a total propane of 1,200 gal/y

 

After HPs: I used 100 gal for DHW + 250 gal for 2 stoves in basement + 550 gal for Viessmann furnace + 2,489 kWh of electricity.

 

My propane cost reduction for space heating was 850 - 550 = 300 gallon/y, at a cost of 2.339/gal = $702/y

My displaced fuel was 100 x (1 - 550/850) = 35%, which is better than the Vermont average of 27.6%

My purchased electricity cost increase was 2,489 kWh x 20 c/kWh = $498/y

 

My energy cost savings due to the HPs were 702 - 498 = $204/y, on an investment of $24,000!!

 

Amortizing Heat Pumps

 

Amortizing the $24,000 turnkey capital cost at 3.5%/y for 15 years costs about $2,059/y.

This is in addition to the amortizing of my existing propane system. I am losing money.

https://www.myamortizationchart.com

 

Other Annual Costs

 

There likely would be service calls and parts for the HP system, as the years go by.

This is in addition to the annual service calls and parts for my existing propane system. I am losing more money.

 

Energy Savings of Propane versus HPs

 

Site Energy Basis: RE folks claim there would be a major energy reduction, due to using HPs. They compare the thermal Btus of 300 gallon of propane x 84,250 Btu/gal = 25,275,000 Btu vs the electrical Btus of 2,489 kWh of electricity x 3,412 Btu/kWh = 8,492,469 Btu.

 

However, that comparison would equate thermal Btus with electrical Btus, which all engineers know is an absolute no-no.

 

A-to-Z Energy Basis: A proper comparison would be thermal Btus of propane vs thermal Btus fed to power plants, i.e., 25,275,000 Btu vs 23,312,490 Btu, i.e., a minor energy reduction. See table 1A

 

BTW, almost all RE folks who claim a major energy reduction from HPs, do not know how to compose this table, and yet they mandate others what to do to save the world from Climate Change.

Table 1A, Energy Savings
Heat in propane, Btu/y, HHV	25275000
Fuel to power plant, Btu/y		23312490
Fuel to power plant, kWh/y		6833
Conversion efficiency		0.4
Fed to grid, kWh		2733
Transmission loss adjustment, 2.4%		2667
Distribution loss adjustment, 6.7%		2489
Heat in propane, Btu/gal, HHV	84250
Purchased propane, gal/y	300
Purchased electricity, kWh/y		2489
Heat in propane Btu/gal, LHV	84250
Standby, kWh		91
Defrost, kWh		154
To compressor, kWh		2244
COP		2.64
Heat for space heat, kWh		5926
Btu/kWh		3412
Furnace efficiency	0.8
Btu/y for space heat	20220000	20220000

PART 2

 

CO2 Reduction due to HPs is minimal

 

My CO2 emissions for space heating, before HPs, were 850 gal/y x 12.7 lb CO2/gal, from combustion = 4.897 Mt/y

 

My CO2 emissions for space heating, after HPs, were calculated in two ways:

 

1) Market based, based on commercial contracts, aka power purchase agreements, PPAs

2) Location based, based on fuels combusted by power plants connected to the NE grid

See Appendix for details.

 

Market Based

 

Per state mandates, utilities have PPAs with Owners of low-CO2 power sources, such as wind, solar, nuclear, hydro, and biomass, in-state and out-of-state.

Utilities crow about being “low-CO2”, or “zero-CO2” by signing PPA papers, i.e., without spending a dime.

Energy Action Network, a pro-RE-umbrella organization, uses 33.9 g CO2/kWh (calculated by VT-DPS), based on utilities having PPAs with low-CO2 power sources.

Using that low CO2 value makes HPs look extra good compared with fossil fuels.

 

My CO2 of propane was 550 gal/y x 12.7 lb CO2/gal, combustion only = 3.168 Mt/y

My CO2 of electricity was 2,489 kWh x 33.9 g/kWh = 0.084 Mt/y

Total CO2 = 3.168 + 0.084 = 3.253 Mt/y

CO2 reduction is 4.897 - 3.253 = 1.644 Mt/y, based on the 2018 VT-DPS “paper-based” value of 33.9 g CO2/kWh

 

Location Based

 

Utilities physically draw almost all of their electricity supply from the high-voltage grid

If utilities did not have PPAs, and would draw electricity from the high-voltage grid, they would be stealing.

ISO-NE administers a settlement system, to ensure utilities pay owners per PPA contract.

 

Electricity travels as electric-magnetic waves, at near the speed of light, i.e., from northern Maine to southern Florida, about 1,800 miles in 0.01 second.

There is no physical basis for lay RE folks to talk about there being a “VT CO2” or a “NH CO2”, etc.

 

All electricity on the NE grid has one value for g CO2/kWh.

ISO-NE, the NE grid operator, calculated that value at 317 g CO2/kWh, at wall outlet, for 2018

 

My CO2 of propane was 550 gal/y x 12.7 lb CO2/gal, combustion only = 3.168 Mt/y

My CO2 of electricity was 2,489 kWh x 317 g/kWh = 0.789 Mt/y

Total CO2 = 3.168 + 0.789 = 3.897 Mt/y

CO2 reduction is 4.897 - 3.897 = 0.939 Mt/y, based on the 2018 “real world” value of 317 g CO2/kWh, as calculated by ISO-NE

 

Cost of CO2 Reduction is ($2059/y, amortizing - $204/y, energy cost savings + $200/y, service, parts, labor) / (0.939 Mt/y, CO2 reduction) = $2,188/Mt, which is outrageously expensive. 

   

https://www.eia.gov/environment/emissions/co2_vol_mass.php

https://afdc.energy.gov/files/u/publication/fuel_comparison_chart.pdf

 

EAN Excessive CO2 Reduction Claim to Hype HPs

 

EAN claims 90,000 HPs, by 2025, would reduce 0.37 million metric ton of CO2, in 2025, or 0.37 million/90,000 = 4.111 Mt/y.

 

EAN achieves such a high value, because EAN assumes 100% displacement of fuel (gas, propane, fuel oil), which is completely unrealistic, because the actual fuel displacement in Vermont houses with HPs was only 27.6%, based on a VT-DPS-sponsored survey of HPs in Vermont, and 35% in my well-insulated/well-sealed VT house, as above stated.

 

The EAN 100% claim would be true, only for highly sealed and highly insulated houses, which represent about 1.5% of all Vermont houses.

In addition, the average Vermont house would need 2 to 3 HPs, at a turnkey cost of at least $20,000, to achieve 100% displacement. See URL

https://www.eanvt.org/wp-content/uploads/2020/03/EAN-report-2020-fi...

 

Table 1/CO2 Reduction	With HP	With HP
Fuel displaced 35%	Electricity	Electricity
	Market based	Location based
Electricity CO2, g/kWh	33.9	317
CO2 of 2489 kWh, Mt/y	0.084	0.789
CO2 of 550 gal of propane, Mt/y	3.168	3.168
Total CO2 with HPs, Mt/y	3.253	3.957
CO2 of 850 gal of propane, Mt/y	4.897	4.897
CO2 reduction, Mt/y	1.644	0.939
.
Fuel displaced 100%
CO2 reduction by EAN, Mt/y	4.111	4.111

 

PART 3

 

This section covers various topics related to HPs

 

HP Operating Cost Per Hour

 

If HPs are operated at low temperatures, they have low COPs, which would result in a greater electricity cost per hour than using the displaced fuel.

See table 3 and page 5 of URL

 

At 27.6% Fuel Displacement: Vermont houses with HPs, operated down to about 28F, would require 2,085 kWh/y, to deliver 21,400,000 Btu, at an average COP of 3.34, to displace 27.6% of space heat, at an electricity cost of $417/y, per VT-DPS survey

 

At 35% Fuel Displacement: My HPs, operated down to 15F, would require about 2,489 kWh/y, to deliver 20,220,000 Btu, at an average COP of 2.64, to displace 35% of my space heat, at an electricity cost of $498/y

 

At 100% Fuel Displacement: My HPs, operated down to -10F, would require about 8,997 kWh/y, to deliver 57,290,000 Btu, at an average COP of 2.07, to displace 100% of my space heat, at an electricity cost of $1,799/y.

 

This would displace 850 gal of propane, at a cost of 850 x $2.339/gal = $1,988/y.

 

My energy cost savings would be 1,988 - 1,799 = $189/y, on an investment of $24,000 !!! 

 

Comments on table 2

 

- Vermont HP data was from VT-DPS survey. See Appendix and table 4

- My HPs were operated down to 15F, which is less than the VT HPs, hence my average COP = 2.64

- Most VT HPs are operated down to about 28F; the traditional space heating system is operated below 28F. See figure 14 of URL

- I can operate down to 15F, because of better insulation and sealing than an average Vermont house.

- If my HPs were operated down to -10F, i.e., 100% fuel displacement, my average COP would be 2.07

https://publicservice.vermont.gov/sites/dps/files/documents/2017%20...

 

BTW, all energy systems engineers, including at EAN, know this, because every engineering college teaches that subject to its students.

Table 2	Vermont HPs	My HPs		Before HPs
Fuel Displacement, %	27.6	35%	100%	Propane
Operation	Down to 28F	Down to 15F	Down to -10F
Purchased electricity, kWh	2085	2489	8997	850	Gal
Standby, kWh	76	91	329	0.8	Efficiency
Defrost, kWh	129	154	557	84250	Btu/gal, LHV
Electricity to HPs, kWh	1880	2244	8111
COP	3.34	2.64	2.07
Space heat, kWh	6279	5926	16791
Btu/kWh	3412	3412	3412
Space heat, kWh	21400000	20220000	57290000	57290000

Highly Sealed, Highly Insulated Housing

 

If I had a highly sealed, highly insulated house, with the same efficient propane heating system, my house, for starters, would use very little energy for space heating, i.e., not much additional energy cost saving and additional CO2 reduction would be possible using HPs

 

If I would install HPs, and would operate the propane system down to 5F (which would involve greater defrost losses), I likely would displace a greater percentage of propane, and might have greater annual energy cost savings; much would depend on: 1) the total energy consumption, which is very little, because of my higher-efficiency house, and 2) the prices of electricity and propane. See Note.

 

I likely would need 3 units at 18,000 Btu/h, at a lesser turnkey capital cost. Their output, very-inefficiently produced (low COP), would be about 34,000 Btu/h at -10F, the Vermont HVAC design temperature.

 

However, any annual energy cost savings would be overwhelmed by the annual amortizing cost, and parts and service costs. i.e., I would still be losing money, if amortizing were considered.

 

NOTE:

 

1) About 1.5 percent of Vermont houses are highly sealed and highly insulated, i.e., suitable for economic use of HPs

2) Vermont’s weatherizing program, at about $10,000/unit, does next to nothing for making energy-hog houses suitable for HPs; it is a social program for poorer people.

 

Table 3 shows, I could have operated my HPs down to about 10F, instead of 15F, and break even regarding hourly cost of operation.

My 35% fuel displacement likely would increase to about 40 percent.

 

Table 3 shows, the cost of space heating at -10F is about 1.95/0.49 = 4 times greater than at 30F, whereas the space heat demand increased 40,000/20,000 = 2 times, due to HPs having low COPs at low temperatures, per Engineering Thermodynamics 101

 

BTW, the electricity draw by all HPs would place a high burden on pocket books and distribution grids, during such cold periods, at about the same time all those EVs would be charging.

 

In table 3, the COPs at low temperatures, 35F to 10F (bold), were adjusted downward for defrost losses.

The COPs, determined by manufacturers in a laboratory, exclude defrost losses, which were about 6.2%, per VT-DPS survey. See Appendix and URL

 

Most RE folks who write about, or analyze HPs: 1) fail to mention those losses, and 2) do not adjust the COPs

https://publicservice.vermont.gov/sites/dps/files/documents/2017%20...

 

Cascading Benefits of a Highly Sealed and Highly Insulated Housing Stock

 

If my house were highly sealed and highly insulated, R-40 or better, R20 basement, etc.:

 

1) The space heat demand would be about 50% of the table values, such as 20,000 Btu/h at -10F

2) The electricity and propane cost would also be about 50% of the table values

3) The burden on the distribution grids and transmission grids would be about 50% less.

4) The need for new power plants and electric grids would be less.

 

All that falls under the heading, “putting the horse before the cart”, i.e., highly efficient housing stock first, then HPs

 

Table 3	Heat	Propane	HP	Elect	Diff.
Outdoor Temp	Demand	Cost	COP	Cost
F	Btu/h	$/h		$/h	$/h
-10	40000	1.39	1.20	1.95	0.57
0	35000	1.21	1.45	1.41	0.20
5	32500	1.13	1.55	1.23	0.10
10	30000	1.04	1.75	1.00	-0.04
15	27500	0.95	1.85	0.87	-0.08
17	26500	0.92	2.14	0.73	-0.19
20	25000	0.87	2.45	0.60	-0.27
30	20000	0.69	3.00	0.39	-0.30
35	17500	0.61	3.30	0.31	-0.30
40	15000	0.52	3.70	0.24	-0.28
47	11500	0.40	4.19	0.16	-0.24
50	10000	0.35	4.40	0.13	-0.21
60	5000	0.17	5.10	0.06	-0.12
70	0

 

Heat Pump Evaluation in Minnesota

 

The image on page 10 of URL shows:

 

1) Increasing COPs of an HP versus increasing outdoor temperatures (blue)

2) The defrost range from 37F down to 10F (yellow)

3) Operation of the propane back-up system from 20F to -20F (green).

 

Such operation would be least costly and would displace propane, that otherwise would be used.

The image shows, HPs are economical down to about 13 F, then propane, etc., becomes more economical; much depends on the prices of electricity and propane.

https://mn.gov/commerce-stat/pdfs/card-air-source-heat-pump.pdf

 

BTW, all of the above has been known for many years, in and out of government.

Ground Source HPs

 

They are widely used in many different buildings in northern Europe, such as Germany, the Netherlands, Denmark, Norway, Sweden and Finland.

 

Their main advantage is the COP does not decrease with temperature, because the ground temperature is constant

GSHPs can economically displace 100% of fuel.

HPs can economically displace at most 50% of fuel; the percentage depends on how well a building is sealed and insulated.

 

The main disadvantage of GSHPs is greater turnkey capital cost, i.e., high amortization cost. See URL

http://www.windtaskforce.org/profiles/blogs/residential-and-other-g...

 

NOTE: It is completely inane for RE folks to mindlessly repeat: "Vermont must have 25,000 heat pumps, by so and so year, to fight Climate Change"

However, is required by the off-the-charts nutty GWSA act, and the Comprehensive Energy Plan, which I think, should be rewritten along REALISTIC lines.

 

In the World-CO2 picture, Vermont is just a dot at the end of this sentence.

 

APPENDIX 1

 

Heat Pump Evaluation in Vermont by VT-DPS

 

VT-Department of Public Service found, after a survey of 77 HPs installed in Vermont houses:

 

- The annual energy cost savings were, on average, $200, but the maintenance and annual amortizing costs would turn that gain into a loss of at least $200.

 

- On average, the HPs provided 27.6% of the annual space heat, and traditional fuels provided 72.4%. These numbers are directly from the survey data.

 

- Owners started to turn off their HPs at about 28F, and very few owners were using their HPs at 10F and below, as shown by the decreasing kWh consumption totals on figure 14 of URL

https://publicservice.vermont.gov/sites/dps/files/documents/2017%20...

 

- On average, an HP consumed 2,085 kWh during the heating season, of which:

 

1) To outdoor unit (compressor, outdoor fan, controls) + indoor air handling unit (fan and supplemental electric heater, if used) to provide heat 1,880 kWh;

2) Standby mode 76 kWh, or 100 x 76/2085 = 3.6%;

3) Defrost mode 129 kWh, or 100 x 129/2085 = 6.2%. Defrost starts at about 37F and ends at about 10F.

 

- Turnkey cost for a one-head HP system is about $4,500; almost all houses had just one HP. See URLs.

 

On average, these houses were unsuitable for HPs, and the owners were losing money.

http://www.windtaskforce.org/profiles/blogs/cost-savings-of-air-sou...

 

NOTE: Coefficient of Performance, COP = heat delivered to house/electrical energy to HP

See page 10 of URL

https://mn.gov/commerce-stat/pdfs/card-air-source-heat-pump.pdf

 

Displaced Fuel Percentage of Vermont Heat Pumps, based on survey

 

As a result of a few years of complaints by various HP users, mainly about energy cost savings being much less than stated on various websites, VT-DPS was ordered by the Legislature to hire a consultant to perform a survey. CADMUS gathered the operating data of 77 HPs at 65 sites, to determine annual energy cost savings of the heat pumps.

 

CADMUS calculated:

 

- Space heat to all sites was 65 x 92 million Btu/site = 5,980 million Btu from all fuels. See URL, page 22

- Heat from HPs was 77 x 21.4 million Btu/HP = 1,648 million Btu. See URL, page 21

- Traditional systems provided 5980 – 1648 = 4,332 million Btu, or 4332/5980 = 72.4% of the total space heat.

https://publicservice.vermont.gov/sites/dps/files/documents/2017%20...

 

The energy cost savings were an average of about $200/HP per year, instead of the $1,200/y to $1,800/y bandied about by RE folks and GMP, VT-DPS, VPIRG, etc. After the CADMUS report, those estimates disappeared from booster websites. See URLs.

 

http://www.windtaskforce.org/profiles/blogs/air-source-heat-pumps-a...

http://www.windtaskforce.org/profiles/blogs/fact-checking-regarding...

http://www.windtaskforce.org/profiles/blogs/vermont-baseless-claims...

 

Table 4/Space heat, per CADMUS		Sites	Million Btu/site	Million Btu	%
Heat to sites		65	92.00	5,980		See URL, page 22
		HPs	Million Btu/HP
Heat from HPs	1648/5980	77	21.40	1,648	27.6	See URL, page 21
Heat from traditional	4332/5980			4,332	72.4
.
			Million Btu/site		%
Heat from HPs, on average	1648/65		25.35		27.6
Heat from traditional, on average	92.00 – 25.35 = 66.65		66.65		72.4
			92.00

 

APPENDIX 2

 

UNDERSTATING CO2 EMISSIONS PER KILOWATT-HOUR TO HYPE EVs AND HEAT PUMPS

https://www.windtaskforce.org/profiles/blogs/some-ne-state-governme...

 

CO2 CALCULATIONS

 

The EPA Proscribes Two Methods for Calculating the CO2 Per Kilowatt-hour

https://www.epa.gov/sites/default/files/2016-03/documents/electrici...

 

Method 1 is “location-based”. It is based on physical conditions, i.e., science-based

The CO2 of each electric power source on an electric grid is calculated, based on fuel consumption.

This method is used by the Independent Systems Operator of New England, ISO-NE.

 

Method 2 is “market-based” It has nothing to do with physical conditions.

The CO2 of each electric power source on an electric grid is calculated, based on EPA emission factors applicable to the electricity of commercial contracts. See page 3 of epa.gov URL

This method is used by the Vermont Department of Public Service.

 

Per international convention, the EPA declared wind, solar, nuclear, hydro, biomass (i.e., wood chip burning), farm methane, etc., as having zero CO2 emissions, for bookkeeping purposes. 

 

NOTE: Electricity travels, as electromagnetic waves, at slightly less than the speed of light, i.e., almost 1860 mile in 0.01 second, i.e., from northern Maine to southern Florida in 0.01 second! The electrons largely vibrate in place at 60 cycles per second.

 

It is nonsense for RE folks to talk of the “Vermont Energy mix”, or the “New Hampshire energy mix”, or to use a “paper PPA energy mix”. These fictitious mixes have no physical basis.

 

BTW, if electricity did not travel that fast, the operation of electric grids would be physically impossible.

 

https://vermontbiz.com/news/2021/may/20/vermont-makes-progress-carb...
https://www.windtaskforce.org/profiles/blogs/poor-economics-of-elec...

 

Method 1, Location-Based

 

NE Grid CO2 Emissions, as calculated by ISO-NE

 

In 2019, about 82% of electricity loaded onto the NE grid was generated in NE, and 18% was imported. See Note and table in epa URL

 

The ISO-NE-calculated CO2 emissions for 2019 = (30.997 million US ton, see iso-ne emissions URL x 2000lb/US ton x 454 g/lb)/ (97,853,000 MWh, NE generation, per epa URL) x 1000 kWh/MWh) = 288 g/kWh, fed-to-grid basis, or 288/0.908 = 317 g/kWh, fed-to-user-meter basis, i.e., consumption based, if total grid loss = 2.5%, NE grid + 6.7%, distribution grids = 9.2%.

 

The grid CO2/kWh will be slowly decreasing as more low-CO2 electricity generators, such as wind, solar, nuclear, hydro, biomass (i.e., wood chip burning), farm methane, etc., are added to the electricity mix of the NE grid. 

 

https://www.iso-ne.com/static-assets/documents/2021/03/2019_air_emi...

https://www3.epa.gov/region1/npdes/merrimackstation/pdfs/ar/AR-1744...

 

NOTE: Since 2004, lower-priced electricity has been imported to serve NE demand; much of it is Canadian hydropower. The CO2 of the imports does not count toward NE grid emissions, by convention, because that CO2 is assumed to be counted in the “jurisdiction of origin”. See URL

https://www.iso-ne.com/about/key-stats/air-emissions

 

Method 2, Market-Based

 

Vermont Electrical Sector CO2 Emissions, as calculated by VT-DPS

  

VT-DPS, without providing any calculations, announced the CO2 emissions of the VT electrical sector were 1,000,000; 810,000; 490,000; 190,000; and 130,000 metric ton, for 2015 through 2019.

See page 36 of URL

https://dec.vermont.gov/sites/dec/files/aqc/climate-change/document...

 

The VT-DPS emissions were almost entirely “market-based”, i.e., based on EPA emission factors applicable to the electricity of power purchase agreements, PPAs

 

VT utilities are legally required to have PPAs with the owners of in-state and out-of-state electricity producers  

 

If VT utilities did not have such PPAs, they would be drawing electricity from the NE grid without contracts, which is the legal equivalent of stealing!

 

Physically, VT utilities draw about 95% of their annual 6.0 billion electricity supply from the NE high voltage grid, i.e., they draw the mix of the NE grid.

The remaining 5% is fed to utility-owned distribution grids, such as rooftop solar. See Note

 

Because of losses, about 5.6 billion kWh/y arrives at user meters, a distribution loss of about 100 x (1- 5.6/6.0) = 6.7%

 

VT-DPS-calculated CO2 emissions for 2019 = 130,000 Mt/y / 5.6 billion kWh/y = 23 g CO2/kWh, fed-to-user-meter basis, i.e., consumption based, or only 100 x {1 - (1 - 23/317)} = 7.3% of the ISO-NE value.

Comments on Image

 

The below graph of the VT electric sector (blue) has been deceptive for many years

 

VT Location-based CO2, in 2019, was about 5.6 billion x 317 g/kWh = 1,773,918 Mt, per ISO-NE fuel data.  

 

VT Market-based CO2, in 2019, was about 130,000 Mt, per PPAs.

 

The market-based method enabled GMP to proclaim itself to be 95% CO2-free, without spending one dime, because it signed PPAs for wind, solar, nuclear, hydro, biomass (i.e., wood chip burning), farm methane, etc., which are designated as having zero CO2 emissions, per international convention.