COST SAVINGS OF AIR SOURCE HEAT PUMPS ARE NEGATIVE IN VERMONT, MAINE, ETC.

Vermont has a Comprehensive Energy Plan, CEP. The capital cost for implementing the CEP would be in excess of $1.0 billion/y for at least 33 years, according to the Energy Action Network annual report. See URLs.

 

http://eanvt.org/wp-content/uploads/2016/04/EAN-2015-Annual-Report-... 

https://outside.vermont.gov/sov/webservices/Shared%20Documents/2016...

 

Spending on government energy programs, including Efficiency Vermont, has averaged about $210 million/y from 2000 to 2015, but Vermont CO2 emissions increased 18% from 1990 to 2015. 

 

CEP Goals for Building Space Heat and Domestic Hot Water

 

63% from renewable electricity (wind, solar, hydro, biomass, etc.)

34% from wood burning (cordwood/pellet) and bio liquids.

3% from fossil fuels burning.

 

The CEP has a goal to install about 35,000 air source heat pumps, ASHPs, by 2025. ASHPs installed were:

 

In 2016, 4118; due to subsidies and boosting

In 2017, 4161; due to subsidies and boosting

In 2018, 2786; CADMUS survey report appeared in November 2017 with bad news for ASHPs.

 

NOTE: The 2018 decrease is likely due to ASHP owners, in energy-hog houses, becoming aware the average energy cost savings would be minimal. If other costs were added (amortizing, service calls, parts, etc.), they would have an annual loss. See URL.

The CADMUS survey of 77 ASHPs, at 65 sites showed Vermont’s free-standing houses with ASHPs would have about 27.6% of space heat from ASHPs and 72.4% space heat from traditional systems.

https://publicservice.vermont.gov/sites/dps/files/documents/EVT%202...

NOTE: Incompetent Efficiency Vermont, one of the major boosters of ASHPs, claiming $1200 - $1800 per year in savings, was assigned to (mis)manage the ASHP program. After many complaints about less-than-promised savings by ASHP owners, it turned out actual energy cost savings averaged only $200/y, per CADMUS/VT-DPS survey. See URL

 

Annual Cost and CO2 Emissions

 

This article shows, an ASHP in an average energy-hog house in VT:

 

27.6% Fuel Displacement (existing conditions, per CADMUS report)

- Provided the owner with a loss of about $220/y. See URL of VT-DPS website

- Required a turnkey capital cost of about $4,500; excludes subsidies.

- Reduced CO2 from 25,111 lb/y to 20,199 lb/y, or 19.6%.

 

If 100% Fuel Displacement

- Would provide the owner with a loss of about $1,759/y.

- Would require a turnkey capital cost of about $20,000 for additional ASHPs; excludes subsidies.

- Would reduce CO2 from 25,111 lb/y to 9,908 lb/y, or 60.5%.

- ASHP electricity demand at -10F would be about 694/93 = 7.5 times greater than at 35F

- ASHP electricity consumption would be about 12210/2470 = 4.94 times greater for 100% space heat from ASHPs than for 27.6% space heat from ASHPs  

- Would impose an additional demand on distribution and high voltage systems of about 1,800 MW at -10F, on a cold winter day, if 166,950 housing units (free-standing, condos, apartments, etc.) had 100% space heat from ASHPs.

 

Table 1 shows, on average, ASHPs in energy-hog houses, are money losers at 27.6% displacement, and bigger losers at 100% displacement.

 

NOTE: If the CEP goal were to "get rid of" fossil fuels and reduce CO2, then ASHPs in energy-hog houses in VT, NH, ME, etc., have been an expensive, ineffectual flop. The same people who dreamt up this flop want to “double down” to implement the Global Warming Spending Act.

 

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

https://publicservice.vermont.gov/sites/dps/files/documents/Energy_...

 

Table 1/Status	Displ. F.O.	F.O. cost	Elect. cost	Energy cost	Amort.	Total	Min. Loss	CO2	CO2	CO2
		$2.75/gal	$0.19/kWh		5%/y, 15y				Reduction	Reduction
	%	$/y	$/y	$/y	$/y	$/y	$/y	lb/y	lb/y	%
Before ASHP	0	2,455	0	2,455	0	2,455		25,111
After ASHP	27.6	1,779	469	2,248	427	2,675	220	20,199	4,912	19.6
After ASHP	100.0	0	2,316	2,316	1,898	4,214	1,759	9,908	15,187	60.5

 

Energy Sources of Vermont Housing Units

 

Vermont has about 265,000 households, of which:

 

About 97,000 use cordwood/pellets for a part or all of space heat.

About 65,000 use cordwood/pellets as primary fuel for space heat.

About 190,000 use No. 2 fuel oil, propane or natural gas as primary fuel for space heat. 

About 10,000 use electricity as primary energy for space heat.

  

Table 2/Housing units	Existing	Existing	Future, per CEP		Future
Source	Description	Units	Source	%	Units
Cordwood/pellets	Primary fuel for space heat	65,000	Cordwood/pellets/biofuels	34	90,100
No. 2 fuel oil, propane or natural gas	Primary fuel for space heat	190,000	ASHPs	63	166,950
Electricity	Primary energy for space heat	10,000	Fossil	3	7,950
Total		265,000		100	265,000

 

Vermont Needs to Enact and Enforce a Strict Building Energy Code

 

If Vermont had enacted and enforced a strict energy code for building in about 1990, or sooner (as many northern European countries did), there would be tens of thousands of houses and other buildings in Vermont that could be economically heated with ASHPs, but Vermont did not!

 

The obvious conclusion is highly sealed and highly insulated houses, with low heat demands at -10F, are absolutely essential for ASHPs to be economically successful.

 

About 88,000 of Vermont's 100,000 free-standing houses are unsuitable for 100% space heat from ASHPs. They would need major energy retrofits, at a cost of about $30,000 per house ($2.7 billion), to reduce their space heat to less than 30,000 Btu/h, at 65F indoor and -10F outdoor, to make them economically suitable for 100% space heat from ASHPs.

 

After major retrofit, each house would need ASHP capacity of at least 30,000 Btu/h, at -10F, or about 65,000 Btu/h at 47F, at a cost of about $20,000 ($1.8 billion), for 100% space heat from ASHPs.

 

About 59,000 of Vermont’s 66,950 apartments, condos, etc., are unsuitable for 100% space heat from ASHPs. They would need the same upgrades.

 

ASHPs in WS/WI and HS/HI and Passivhaus houses would economically provide 100% of space heat from 65F to -10F. 

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

 

Passivhaus Standard

 

The Passivhaus standard, conceived in 1988, is the gold standard regarding space heat. All other houses are much worse. 

 

Passivhaus-type housing were difficult to build, but lighting, appliances, heating, sealing, insulation, windows, doors, etc., have advanced to make it much easier during the last 15 years.

 

Table 3/Vermont	Built		Area	Htg. Demand	Pk. Demand	Times	Air Leak	ACH
Unsuitable for ASHPs		%	ft2	(Btu/h)/ft2	Btu/h at -10F	Passiv	ft3/min	@ -50 pascal
Typical older house	1750 - 1990	68.4	2000	40.0	80,000	12.6	2667	10.0
Newer house	1990 - 2000	10.0	2000	24.0	48,000	7.6	1600	6.0
Newer house, IECC	2000 - 2012	10.0	2000	20.0	40,000	6.3	1867	7.0
Suitable for ASHPs
"WS/WI house", IECC+	2012 - 2021	10.0	2000	15.0	30,000	4.7	800	<3.0
“HS/HI house”, IECC++	2000 - present	1.5	2000	8.5	17,000	2.7	400	<1.5
Passivhaus, IECC+++	1985 - present	0.1	2000	3.2	6,348	1.0	160	<0.6
		100.0

 

CADMUS SURVEY OF HOUSES WITH ASHPs

 

CADMUS, an energy consultant hired by the Vermont Department of Public Service in 2017, performed a survey of 77 ASHPs at 65 sites in Vermont.

 

It uses a standard HVAC computer program that takes the hourly temperature history of a heating season (obtained from weather data), and allocates the frequency and duration of temperatures to two-degree temperature slots, also called “bins”. See horizontal line of figure 14.

The heat to a site is calculated for each bin, say 34F - 36F.

The total heat to a site is obtained by adding the heats for all temperature bins.

 

72.4% of Space Heat from Traditional Systems and 27.6% from ASHPs 

 

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 ASHPs was 77 x 21.4 million Btu/ASHP = 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/EVT%202...

 

No wonder the energy cost savings were an average of about $200/ASHP per year, instead of the $1200/y to $1800/y bandied about by 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
		ASHPs	Million Btu/ASHP
Heat from ASHPs	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 ASHPs, 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

 

Capital and Annual Operating Costs Result in an Overall Annual Loss

 

CADMUS/VT-DPS concluded, on average, an owner invested $4500 in an ASHP (less with subsidies), but had average energy cost savings of about $200/y; some had more savings than others.

 

Amortizing $4500/ASHP at 5%/y for 15 years (the factory warrantee is for 10 years), the annual payments would be $427.03/y. 

https://www.myamortizationchart.com

 

In addition, there would be annual costs for scheduled and unscheduled service calls ($100+/call, plus parts), plus annual costs for maintenance contracts ($100+/contract, plus parts).

 

Those costs would be in addition to amortizing the cost of the existing traditional heating system investment over 15 years, plus the annual cost of service and maintenance.

 

Independent energy systems engineers predicted installing ASHPs in energy-hog houses would result in an annual loss to owners, if overall costs of having two heating systems were accounted for, some years ago, but ASHP boosters were busy chasing CEP goals, collecting subsidies, creating jobs and making profits.

 

ANALYSIS

 

Building Space Heat Demand and ASHP Space Heat Supply  

 

See URL of CADMUS report, figure 14

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

  

ASHP Space Heat Supply From 70F to about 35F 

Figure 14 shows, ASHPs started to show some heat supply at about 68F. See orange line, right side

It appears, the ASHPs are capable to satisfied 100% of building space heat demand, Btu/h, until about 35F

If the ASHPs had more capacity, their electricity demand, kW, and heat supply, Btu/h, would have increased, as it became colder.

However, kW and Btu/h did not increase, as shown by figure 14.

  

ASHP Space Heat Supply From 35F to -10 F

Figure 14 shows, space heat demand of all buildings is about 1,016,380 at 35F, and greater at 26F. See Note.

Electricity consumption by ASHPs remained about the same.

Heat from ASHPs decreased from 35F to 26F, while the building heat demand steadily increased, as it became colder.

 

That means, owners started to turn off ASHPs and turn on traditional heating systems at temperatures below 35F, to provide the heat difference, i.e., (building space heat demand – ASHP heat supply).

 

Cold-climate heat pumps should not be called cold-climate heat pumps, because in Vermont (and likely in Maine, New Hampshire, etc.), owners with ASHPs in energy-hog houses, turned off ASHPs at colder temperatures, i.e., they are not used at colder temperatures, except in the very few houses that are suitable, such as WS/WI, HS/HI, and Passivhaus houses.

  

ASHP Space Heat Supply at -10F

Heat demand of all buildings is about 2,323,154 Btu/h. Figure 14 shows, ASHP heat supply was near zero at -10F, i.e., almost all owners had turned off ASHPs, and had turned on traditional systems. See Note.

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

 

NOTE: Whenever it was 35F outdoor during the heating season, heat from 77 ASHPs was (93 – 5.4, overhead) kW x 3.4, COP x 3412 (Btu/h)/kW = 1,016,380 Btu/h (orange curve, right axis), or an average of 13,200 Btu/h per ASHP.

CADMUS created the orange curve by making a calculation for each temperature.

 

If we draw an upward-sloping, straight line from 70F to 35F, the building heat demand increases from 0 Btu/h at 70F to 1,016,380 Btu/h at 35F. The slope of the line, is 1016380/(70F – 35F) = 29,039 Btu/h/F

 

Heat demand of all buildings would be 29,039 x (70F to -10F) = 2,323,154 Btu/h at -10F, the 99% design temperature for Vermont.

 

NOTE:

Using table 3 for pro-rating (See URL), the rated output of all ASHPs could be about 77 x 7662 Btu/h at -10F = 590,000 Btu/h at -10F. However, Figure 14 shows, the actual ASHP output was near zero, i.e., ASHPs were turned off.

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

 

The 65 sites would need significant additional ASHP capacity, Btu/h, to provide 100% of space heat at -10F, because.

space heat demand of all sites would be 2,323,154/590,000 = 4.2 times greater than the existing ASHPs would be able to provide. 

 

Table 5/ Space heat demand
Space heat demand of all sites, Btu/h @ 70F		0
Space heat demand of all sites, Btu/h @ 35F		1,016,380
Slope of space heat demand line	1016380/(70F - 35F)	29,039
Space heat demand of all sites, Btu/h @ -10F	29039 x {70F - (-10F)}	2,323,154

 

Turnkey Capital Cost of ASHPs/site for 27.6% and 100% Space Heat by ASHPs

 

- In rounded numbers, the capacity of the ASHPs must be about 4.7 million Btu/h at 47F, to have an output of about 2.35 million Btu/h at -10F, equal to the space heat demand of all sites at -10F.

- On average, each site would need an ASHP capacity with an industry standard rating, of about 4.7 million/65 = 72,308 Btu/h at 47F

- On average, allowing for deterioration of output over time, each site would need an ASHP capacity with an industry standard rating of about 75,000 Btu/h at 47F, at a turnkey capital cost of about $20,000/site, or $1.3 million for all sites.

- The capital cost of the existing ASHPs of about $346,500 for 27.6% ASHP heat, would increase to about $1,300,000 for 100% ASHP heat.

- DHW heat supply is a separate issue, because ASHPs typically do not provide DHW.

 

Table 6/Turnkey capital cost
Heat from ASHPs, %	27.6		100
Space heat demand of all buildings at 35F, Btu/h	1,016,380
Space heat demand of all buildings at -10F, Btu/h			2,323,154
Rounded, Btu/h at -10F, Btu/h			2,350,000
Required ASHP capacity at 47F, Btu/h			4,700,000
.
ASHPs	77	Sites	65
Average output/ASHP at 35F, Btu/h	13,200	ASHP capacity at 47F, Btu/site	72,308
Capital cost, $/ASHP	4,500	Capital cost/site. $/site	20,000
Total turnkey capital cost, $	346,500	Total turnkey capital cost, $	1,300,000

 

Electricity Demand of ASHPs

 

The 27.6% of heat from ASHPs to 65 sites was about evenly divided from 65F to 35F, and from 35F to -10F. See URL, figure 14, orange curve.

 

The warm part was at high COPs, the cold part was at low COPs.

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

 

The 72.4% of heat from additional ASHPs to 65 sites would be mostly provided from 35F to -10F, the cold part, with low COPs, low Btu/kWh, and with more kWh for defrosting, which occurs during lower temperatures.

 

For 100% space heat from ASHPs, electricity demand at -10F would be about 694/93 = 7.5 times greater than at 35F

 

Table 7/Electricity Demand of ASHPs		27.6% heat from ASHPs	100% of heat from ASHPs
Temperature	F	35F	-10F
Draw of 77 ASHPs at 65 sites, kW; CADMUS	kW	93
.
Rated capacity of ASHPs at 47F, all sites	Btu/h		4,700,000
Required capacity of ASHPs at -10F, all sites	Btu/h		2,350,000
Conversion factor	Btu/kWh		3412
COP at -10F			1.1
Draw for 100% heat from ASHPs at -10F	kW		626
Standby/defrost loss factor; 2085/1880; CADMUS			1.109
Draw for 100% heat from ASHPs at -10F	kW		694
Draw ratio, 694/93			7.5

 

Future ASHP Electricity Demand, if 100% Space Heat from ASHPs in Vermont Houses

 

Future ASHP demand would impose a demand on distribution and high voltage systems, in addition to future EV demand.

 

Vermont has about 265,000 housing units

 

After major retrofit, about 100,000 of Vermont's free-standing houses with ASHPs would have a demand of about 100,000 x 694 kW/55 sites = 1,262 MW at -10F, on a cold day in winter.

 

After major retrofit, about 66,950 non-free-standing housing units (apartments, condos, etc.) with ASHPs would have a demand of about 66,950 x 8 kW = 536 MW at -10F, on a cold winter day

 

Those demands would be in addition to the existing Vermont demand of about 1000 MW.

 

The remaining 98,050 housing units would use cordwood/wood pellets, or biofuels, or electric resistance heating.

 

NOTE: Major upgrading (“deep retrofits”) of the energy efficiency of at least 88% of all Vermont buildings would be required, if 100% space heat from ASHPs.

 

NOTE: ASHPs usually do not provide heat for DHW, i.e., separate systems would be required.

 

Annual Electricity Consumption by ASHPs

 

On average, existing ASHPs supplied 25,350,000 Btu/y to a site, or 27.6% of space heat, at a COP of about 21,400,000/7,114,020 = 3.0, per CADMUS.

Electricity for 27.6% heat from ASHPs to a site would be 25,350,000 Btu/y x (2085 kWh/21,400,000 Btu/y) = 2,470 kWh/y

 

On average, additional ASHPs would provide 66,650,000 Btu/y to a site, or 72.4% of space heat, at colder temperatures and lower COPs, say 2.0

Electricity to these ASHPs would be at least 72.4/27.6 x 3/2, COP adjustment factor x 2470 kWh/y = 9,741 kWh/y

 

Electricity for 100% heat from ASHPs to a site would be 2470 kWh/y, existing + 9,741 kWh/y, additional = 12,210 kWh/y.

 

ASHP electricity consumption at -10F would be about 12210/2470 = 4.94 times greater for 100% space heat from ASHPs than for 27.6% space heat from ASHPs  

 

Table 8	ASHPs	ASHPs
Heating, %	27.6%	100%
27.6% of space heat from ASHPs to a site, Btu/y, per CADMUS	25,350,000
Electricity to one ASHP, kWh/y, per CADMUS	2085
Heat from one ASHP, kWh/y; per CADMUS	21,400,000
Electricity to ASHPs of a site, kWh/y	2470
COP	3.0	1.5
72.4% of space heat from additional ASHPs to a site, kWh/y		9741
100% of space heat from ASHPs to a site, kWh/y		12210
Electricity consumption ratio; 12210/2470		4.94

 

CO2 REDUCTION AND COST; source energy basis; downstream ignored

 

The below calculations are for a typical house with an oil-fired traditional system and one ASHP.

 

100% Heat from Traditional Systems

- Purchased fuel oil for a site was 892.9 gal/y

- CO2 from fuel oil was 25,123 lb CO2/y, source energy basis

 

 27.6% Heat from ASHPs, 72.4% Heat from Traditional Systems

- Fuel oil heat to a site was 0.724 x 92,000,000 = 66,350,000 Btu/y, per CADMUS. See table 6

- Available heat 66,350,000 Btu/y / 137,381 Btu/gal was equivalent to 485.1gal/y

- Purchased fuel oil was 485.1/0.7, seasonal efficiency = 646.9 gal/y

- Heat from ASHPs was 92,000,000 - 66,350,000 = 25,350,000 Btu/y

- Electricity to ASHPs was 25,350,000/21,400,000 x 2085 = 2,470 kWh/y, per CADMUS 

- Reduction of purchased fuel oil for heat was 246 gallon/y. 

- Reduction of CO2 was 4912 lb/y; source energy basis; downstream ignored. See table 6.

 

100% Heat from ASHPs

- Electricity for 100% heat would be 12,210 kWh/y. CO2 emission 9,924 lb/y

- Heat to a site would be 92,000,000 Btu/y, per CADMUS

- Reduction of purchased fuel oil for heat would be 892.9 gallon/y

- Reduction of CO2 would be 15,187 lb/y; source energy basis; downstream ignored

 

If 27.6% of space heat were from ASHPs installed in average Vermont energy-hog houses, CO2 reduction would be from 25,123 lb/y (at 100% fuel oil) to 20,129 lb/y, or 19.6%

 

If 100% of space heat were from ASHPs installed in average Vermont energy-hog houses, CO2 reduction would be from 25,123 lb/y (at 100% oil) to 9,908 lb/y, or 60.5% 

 

The results of CO2 reduction calculations are summarized in table 9.

 

NOTE:

US ton = 2000 lb

Metric ton = 2204.62 lb

 

NOTE:

- Almost the entire VT building stock would have to upgraded to at least well-sealed/well-insulated, at a multi-billion-dollar capital cost, to make them suitable for 100% space heat with ASHPs.

- In colder climates, buildings would need to have major energy retrofits to reduce their space heat to less than 15.0 Btu/h/ft2, at 65F indoor and -10F outdoor, to make them economically suitable for 100% space heat with ASHPs.

- Passivhaus-style buildings are an attractive alternative over energy-hog buildings, on a lifetime basis. See Appendix.

 

Table 9/CO2 Reduction		Before ASHP	After ASHP	After ASHP
No. 2 Fuel oil		100% Fuel oil	72.4% Fuel oil	0 % Fuel oil
Purchased fuel oil	gal/y	892.9	646.9
Annual average efficiency		0.75	0.75
Available heat	gal/y	669.7	485.1
.
ULS, <50 ppm S, fuel oil
Higher heat value	Btu/gal	137,381	137,381
Lower heat value	Btu/gal	131,579	131,579
Heat to one site, per CADMUS	Btu/y	92,000,000	66,650,000
.
Combustion CO2	kg/gal	10.21
	lb/kg	2.205
Combustion CO2	lb/gal	23.509
Upstream CO2, 25% of combustion	lb/gal	5.627
Total CO2, SE basis	lb/gal	28.123
Fuel oil CO2	lb/y	25,111	18,192	0
.
Purchased electricity; table 5	kWh/y		2,470	12,210
CO2, NE grid, wall meter, SE basis	g/kWh		369	369
CO2, NE grid, wall meter, SE basis	g/y		911,374	4,505,490
	g/lb		454	454
CO2, NE grid, wall meter, SE basis	lb/y		2,007	9,924
Total CO2, NE grid, wall meter, SE basis	lb/y	25,111	20,199	9,924
CO2 reduction	lb/y		4,912	15,187
CO2 reduction	%		19.6	60.5
.
Fuel cost at $2.75/gal	$/y	2,455	1,779
Electricity cost at $0.19/kWh	$/y		469	2,320
Capital cost	$		4,500	20,000
Amortizing at 5%/y for 15 y	$/y		427	1,898
Total cost	$/y	2,455	2,675	4,218
Loss	$/y		220	1,763

ASHP SAVINGS WITH AND WITHOUT CARBON TAX

 

Without Carbon Tax

 

Before ASHP: An owner spends for space heat 892.9 x $2.75/gallon (buyer’s club price) = $2,455/y.

 

After ASHP: An owner spends for space heat 642.9 x $2.75/gallon= $1769/y, plus for electricity 2470 x 0.19 c/kWh, incl. taxes, fees, surcharges = $469/y, for a total of $2,238/y, an energy cost saving of $217/y, which is close to the $200/y average energy cost saving of the CADMUS survey. See table 7.

 

Amortizing $4500/ASHP at 5%/y for 15 years (the factory warrantee is for 10 years), the annual payments would be $427.03/y.

https://www.myamortizationchart.com

 

In addition, there would be annual costs for scheduled and unscheduled service calls ($100+/call), plus annual costs for maintenance contracts ($100+/contract), both likely involving parts and labor.

 

Those costs would be in addition to amortizing the cost of the traditional heating system investment over 15 years, plus the annual cost of service calls and annual cost of maintenance contracts.

 

With Carbon Tax

 

Table 7 shows the effect on ASHP annual savings, if a carbon tax of $1.50/gallon is imposed.

The heating bill of owners without ASHPs increased to $3795/y.

The heating bill of owners with ASHPs increased to $3209/y.

The ASHP energy cost savings were $586/y.

 

Table 7/Annual Savings		Without carbon tax	Without carbon tax	With carbon tax	With carbon tax
		Before ASHPs	After ASHPs	Before ASHPs	After ASHPs
Purchased fuel oil	gal	892.9	642.9	892.9	646.9
Fuel oil price	$/gal	2.75	2.75	4.25	4.25
Fuel oil cost	$/y	2455	1768	3795	2749
Electricity to ASHPs	kWh/y		2470		2470
Electricity price	$/kWh		0.19		0.19
Electricity cost	$/y		469		469
Total cost	$/y		2237		3218
Energy cost saving	$/y		218		576

APPENDIX 1

Net Zero Passive Houses Are the Answer to Housing Energy Efficiency

https://news.bloombergenvironment.com/environment-and-energy/insigh... 

 

The energy savings from net zero passive houses can reduce heating costs by 75% to 90%, and these new dwellings have a much longer life span, writes Passive Design Solutions’ Natalie Leonard. She says ensuring that all new structures achieve significant and permanent energy reductions will require financial incentives to facilitate the replacement of existing homes.

 

The building sector accounts for 50% of all energy used in North America but has not achieved significant improvements in energy efficiency and carbon emissions like that of the transportation and durable goods sectors.

 

One part of the building sector deserving attention is detached single-family housing. In 2018 the U.S. had about 83 million detached houses and Canada had about 7.67 million. From January to September 2019 there were 653,300 single‐unit housing completions in the United States, and 45,086 single-family house completions in Canada.

 

Retrofitting existing houses is expensive and may, at best, only result in energy savings of 30% compared to other dwellings in the same location that have not been retrofitted. On the other hand, the energy savings of new construction can reduce heating costs by 75% to 90%. Moreover, new buildings have a much longer life span over which to amortize and enjoy the additional energy and cost savings.

 

Simply renovating existing houses to improve their energy efficiency, although important, does not give optimal results. Nor is it the most cost-effective approach in every instance.

 

The Gold Standard for Optimizing the Energy Efficiency of an Existing House is its Replacement.

 

At first, this may seem excessive. However, there is a rationale for this approach, and it has to do with the rather slow rate at which older, less energy efficient housing is replaced with new, more energy efficient housing.

 

Given the large inventory of new and existing detached houses, it is clear that any public policy intending to make meaningful reductions to national building energy use must address this housing sector. A net zero passive house replacement can provide significant energy savings, with a design that is durable and low maintenance.

 

Net Zero Passive Houses 

 

Net zero is defined in a number of ways. A useful definition says that a net zero building is one with zero net energy consumption, meaning the total amount of energy used by the building on an annual basis is equal to the amount of renewable energy created on the site. 

Passive house is a voluntary standard for energy efficiency in a building, which reduces the building’s ecological footprint. It results in ultra-low energy buildings that require little energy for space heating or cooling. 

 

Net zero houses are not necessarily passive designs, and passive houses are not necessarily net zero. But augmenting passive house design with modest on-site, grid-tied electrical power generation provides a simple path to net zero that can be implemented for a modest premium: 5% to 15% over code-built alternatives. And they achieve a 75%-90% reduction in heating costs, with annual heating bills as low as $150.00. 

 

Canada’s National Energy Code for Buildings (NECB) 2017 says the “most cost-effective time to incorporate energy efficiency measures into a building is during the initial design and construction phase. It is much more expensive to retrofit later. This is particularly true for the building envelope”, which is the single most important element of an energy efficient dwelling.

 

The Environmental Change Institute at Oxford University has argued that between 2005 and 2050, 3.2 million dwellings must be demolished and replaced for the U.K. to reach its national energy reduction targets for housing. 

The Oxford research recognizes that some dwellings require prohibitively expensive repairs before energy reduction measures can be implemented, and even then, the results are unimpressive.

 

Low-Income Energy Efficiency Program (LIEEP) contractors in Maryland found significant pre-existing health and safety deficiencies in houses identified for efficiency improvements. The improvements could not proceed until repairs were completed.

 

Many Attractive Benefits of Net Zero Passiv Houses

 

A net zero passive house is not a “new-age” compromise. Instead, it is a versatile housing solution that provides a number of attractive benefits:

 

• Significant reduction in heating costs over code-built houses;
• Reduced carbon footprint;
• Superior indoor comfort—the bright, draft-free and consistently warm spaces are what owners most love about their passive house;
• Exceptionally quiet spaces that are isolated from outside noise, even during storms;
• Less complex operational and maintenance requirements due to simpler mechanical systems;
• Comfortable, conditioned fresh air in the living spaces through the use of high-quality ventilation equipment;
• Increased safety and security during storms: even when power is out for weeks, a passive house will maintain temperatures above 50F (10C).

 

Financial Incentives Needed for Adoption

 

Providing financial incentives for the adoption of net zero passive house technologies will hasten acceptance by the marketplace and its adoption into the building code, and in our uncertain climate future, this is good public policy.

 

A net zero passive house is slightly more expensive to build, but excels in the total cost of ownership, a fact not always well understood. Hence, without some inducement, the higher up-front cost of net zero passive houses can present a disincentive to their adoption. Financial incentives can help to overcome this reluctance.

 

Research in North America shows that financial incentives are particularly effective in overcoming the public’s reluctance to switch to energy-efficient technologies such as the net zero passive house.

 

Research in Europe showed similar findings “financial incentives and energy performance standards play an important role in promoting energy efficiency improvements.”

 

It seems likely that increasing the energy efficiency of new and existing North American detached homes will require public intervention. A good first step is changing building codes to emphasize net zero passive house level energy efficiency. Such code changes will ensure that all new structures achieve significant and permanent energy reductions. These code changes should be accompanied by financial incentives to facilitate the transition.

 

Author Information

 

Natalie Leonard, P. Eng., is a certified passive house consultant and certified passive house builder.

As an engineer and the president of Passive Design Solutions, she has completed over 100 passive house projects that are net zero ready. Committed to reducing the housing industry’s notable carbon footprint, the team has recently launched a line of ready-to-build passive house design plans, available online to the general population.

 

APPENDIX 2

CO2 of NE Grid Electricity

 

ISO-NE publishes an annual CO2 report.

The 2019 report has the 2017 data.

The 2020 report, in draft form, has the 2018 data. 

I am using the 2018 data. See URL, page 13.

 

ISO-NE uses PE to calculate CO2/kWh, i.e., fuel/energy fed to power plants.

ISO-NE does not include upstream energy to calculate CO2/kWh.

Upstream CO2/kWh of NE grid is about 10.2% of PE CO2/kWh.

https://www.iso-ne.com/static-assets/documents/2020/01/draft_2018_e...

 

Fed to grid, 299 g CO2/kWh, PE basis, becomes 299 x 1.102 = 329 g CO2/kWh, SE basis.

Fed to wall meters, 321 g CO2/kWh, PE basis, becomes 321 x 1.102 = 354 g CO2/kWh, SE basis.

 

For analysis purposes, with, in the future, millions EVs simultaneously charging all over NE, 354 g/kWh should be used for any electricity from any wall meter in NE.

 

That takes the unscientific rah-rah factor about "our Vermont grid mix is cleaner than yours", out of the equation. See Appendix.

 

NOTE: If battery charge change is used for calculating CO2:

 

CO2 would be 0.4553, wall meter readings / 0.3500, battery readings x 321 = 418 g/kWh, PE basis

CO2 would be 1.3 x 354 = 461 g/kWh, SE basis. See URL for 1.3 factor

http://www.windtaskforce.org/profiles/blogs/comparison-of-tesla-mod...

 

Table 14 shows:

 

The source energy required for a quantity of electricity at user wall meters.

The values for the Tesla vehicles were based on real-world conditions for a year.

The value for NE LDVs was based on an LDV mix using, on average, 0.350 kWh/mile from the battery.

The mix would include cars, cross-overs, SUVs, minivans and 1/4-ton pick-ups, all sizes.

 

NOTE: 

Most non-engineer analysts of EVs do not use real-world values for upstream energy and driving energy.

Often, they omit the charging loss and self-use loss and their CO2.

Often, they do not ratio upwards wall meter / vehicle meter

Their faulty analysis leads to lesser calculated values of kWh/mile and CO2/mile.

That likely leads to rosy thinking regarding EVs, faulty decision-making and energy policies

 

Table 14/NE grid for 2018	LDV mix	Tesla	Tesla	NE grid CO2	NE grid CO2
		Model S	Model 3	PE	SE
	kWh/mile	kWh/mile	kWh/mile	gram/kWh	gram/kWh
Source energy	1.2291	1.1713	0.8315
Upstream for extraction, processing, transport, etc., 10.2%	0.1138	0.1084	0.0770
Primary energy	1.1153	1.0629	0.7545
Efficiency loss, 55.5%	0.6078	0.5793	0.4112
Gross electricity generation	0.5075	0.4836	0.3433
Plant self-use loss, 3.0%	0.0152	0.0145	0.0103
Net electricity generation = Fed to grid	0.4922	0.4691	0.3330	299	329
T&D loss, 7.5%	0.0369	0.0352	0.0250
Fed to wall meters, as AC	0.4553	0.4339	0.3080	321	354
Charging loss, 15% of WM	0.0683	0.0651	0.0462
Loss due to self-use loss, road/climate, about 8% of WM	0.0370	0.0359	0.0169
In battery a mix of LDVs in NE, as DC	0.3500	0.3329	0.2449	418	461
.
Travel, miles/y	12000	15243	11174
Wall meter electricity, kWh/y	5475	6614	3442
2 EVs	10950

 

APPENDIX 3

Household Capital Cost to Partially Implement the CEP

An up-scale, “eco-conscious” household, in a 2000 sq ft house, would have to make periodic investments to be “somewhat green”, on a long-term basis. See table 10.

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

 

Table 10/ “Save the World” investments	Cost, $	Life, y
EV, Tesla Model 3, 4-wd; range 322 miles	56,000	10
Energy upgrade, insulation, sealing, windows, doors, etc.	30,000	100
ASHP capacity for 100% space heat at -10F	20,000	10 to 15
Solar panels, 6 kW, production 7500 kWh/y	20,000	25
Batteries for outages	8,000	10
Total per household	134,000
Total all households, excludes financing costs and subsidies	16.75 billion

 

APPENDIX 4

Calculation of Electrical Sector CO2

 

CO2 Based on Physics, per ISO-NE

 

Any time a user draws electricity via a wall socket, it would have the NE mix of electricity.

CO2 of 321 g/kWh, PE basis, wall meter basis, in 2018. 

  

The Vermont grid load is about 6 billion kWh/y

The user demand at wall sockets is about 6 x (1 – 0.075) = 5.55 billion kWh/y

CO2 associated with user demand would be 5.55 billion kWh x 321 g/kWh x 1 lb/454 g x 1 Mt/2204.62 lb = 1,779,953 Mt/y, PE basis, wall meter basis, in 2018

 

CO2 Based on “Paper” PPAs, per VT-DPS

 

VT-DPS definition of “Vermont electricity mix”, based on power purchase agreements, PPAs, yields an artificial “paper” value for CO2/kWh.

 

VT-DPS estimated the artificial “paper” CO2 of the Vermont electricity sector at 190,000 Mt/y in 2018, or 190000/1779953 x 321= 34 g/kWh, PE basis, wall meter basis. See URL and Appendix.

 

The artificial, “paper” value for CO2 would make ASHPs and EVs appear very clean compared to gasoline vehicles.

Political chicanery is going on to promote ASHPs and EVs.

https://greenmountainpower.com/2018/12/13/fuel-mix/

 

NOTE: It would be helpful, if VT-DPS would post its assumptions and calculations on its website, instead of just pronouncing the CO2 and giving it to VT-ANR for insertion into its annual VT CO2 report.

 

NOTE: See URL for GHG estimates for 2017 and 2018

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

 

APPENDIX 5

Electricity Moves as Electro-Magnetic Waves at Nearly the Speed of Light

 

Electricity Mix Based on Power Purchase Agreements: There are non-technical people talking about the “Vermont electricity mix” or the “New Hampshire electricity mix”. That mix exists only on paper, because it is based on power purchase agreements, PPAs, between utilities and owners of electricity generators.

 

A utility may claim it is 100% renewable. This means the utility has PPAs with owners of renewable generators, i.e. wind, solar, biomass, hydro, etc. That mix has nothing to do with physical reality.

 

If a utility did not have PPAs and drew electricity from the grid, it would be stealing, just as a person would be by bypassing the utility electric meter.

 

Entities, such as VT-DPS, should not use PPAs to calculate the g CO2/kWh and the CO2 of the VT electrical sector.

 

Electricity Mix Based on Physical Reality: Once electricity is fed into the NE electric grid by any generator, it travels:

 

- On un-insulated wires, as electromagnetic waves, EM, at somewhat less than the speed of light, i.e. from northern Maine to southern Florida, about 1800 miles in 0.01 of a second, per College Physics 101.

- On insulated wires, the speed decreases to as low as 2/3 the speed of light, depending on the application.

 

If those speeds were not that high, the NE electric grid would not work, and modern electronics would not work.

 

The electrons vibrate at 60 cycles per second, 60 Hz, and travel at less than 0.1 inch/second; the reason it takes so long to charge a battery.

 

It is unfortunate most high school teachers told students the electrons were traveling.

Teachers likely never told them about EM waves, or did not know it themselves.

http://www.djtelectricaltraining.co.uk/downloads/50Hz-Frequency.pdf

 

This article explains in detail what happens when electricity is fed to the grid.

http://www.windtaskforce.org/profiles/blogs/popular-misconceptions-...

 

Entities, such as VT-DPS, should use the ISO-NE estimated g CO2/kWh, at user wall sockets, to calculate the g CO2/kWh and the CO2 of the VT electrical sector.

 

Living Off the Grid

 

- If you live off the grid, have your own PV system, batteries, and generator for shortages and emergencies, then you can say I use my own electricity mix.

- If you draw electricity from a wall socket, you draw the NE mix, per Physics 101.

 

APPENDIX 6

GMP Purchased Electricity Mix

 

GMP electricity mix for 2017, 2018, and 2019, based on PPAs, i.e., paper contracts. 

GMP increased purchases of large hydro and nuclear, which have very low prices/kWh and very low CO2/kWh.

GMP decreased purchases on the wholesale market, which had 299 g CO2/kWh in 2018, fed to grid basis, PE basis.

 

GMP’s paper PPAs with producers of hydro and nuclear did not physically reduce any CO2 anywhere.

GMP is required to have such PPAs to satisfy state-RES mandates.

GMP did not need to spend any money to make any changes in its operations to reduce CO2; sacrifices to “fight global warming” are for little people.

 

VT-DPS uses these PPAs, and PPAs of other VT utilities, to calculate the paper CO2/kWh of Vermont’s electricity sector.

 

I repeatedly asked GMP to fill in the missing data in the table, but so far only stonewalling.

 

Table 13/GMP Electricity Mix	2017	2018	2019
	%	%	%
Large hydro	23.7	49.4
Existing VT hydro	6.3	6.3
Total hydro	30.0	55.7	60.6
Wholesale market purchases	30.4	28.2	9.8
Nuclear	14.7	14.7	27.9
Oil and natural gas	0.5	0.4
Methane	0.7
Hydro	5.5
Solar	5.2	0.9	1.7
Wind	8.0
Wood	5.0
Total RE	24.4	0.9	1.7