Net-Zero Energy HousesNet-Zero Energy Housesand Officesand Offices
……a vision of the future?a vision of the future?Sustainable Operations 19 Nov 08Sustainable Operations 19 Nov 08
Webinar PresentationWebinar PresentationFPL, Madison, WIFPL, Madison, WI
by by Mel Tyree Mel Tyree BA PhD LLD FRSCBA PhD LLD FRSC
NRS-10NRS-10
The Globe & MailThe Globe & Mail28 June 200828 June 2008
The energy content of 1 barrel of oil = the The energy content of 1 barrel of oil = the energy content of 8.6 years of human labor.energy content of 8.6 years of human labor.
Think about it.Think about it.A human lifespan could produce the energy of A human lifespan could produce the energy of about 3 barrels of oil in usable work or impact on about 3 barrels of oil in usable work or impact on the world (@ 10 h of work per day).the world (@ 10 h of work per day).CONCLUSION: human-kind has dominated life CONCLUSION: human-kind has dominated life on earth thru the unfair advantage of fossil fuels. on earth thru the unfair advantage of fossil fuels. What is our future when this advantage (fossil What is our future when this advantage (fossil fuel) is gone?fuel) is gone?
Energy cost of buildings in CanadaEnergy cost of buildings in Canada
30% of Canada’s energy consumption30% of Canada’s energy consumption
50% of Canada’s electricity consumption50% of Canada’s electricity consumption
28% of Canada’s greenhouse gases28% of Canada’s greenhouse gases
Energy cost of buildings in CanadaEnergy cost of buildings in Canada
30% of Canada’s energy consumption30% of Canada’s energy consumption
50% of Canada’s electricity consumption50% of Canada’s electricity consumption
28% of Canada’s greenhouse gases28% of Canada’s greenhouse gases
With declining fossil fuels and rising prices,With declining fossil fuels and rising prices,
WHAT MIGHT THE HOUSING FUTURE WHAT MIGHT THE HOUSING FUTURE BE?BE?
My Net-Zero Energy House(Also zero emission house)
My Net-Zero Energy House(Also zero emission house)
This house will save a projected $165,000 in fuel and energy costs. Over the next 20 years.
My Net-Zero Energy House(Also zero emission house)
This house will save a projected $165,000 in fuel and energy costs. Over the next 20 years.
AND IT COST ONLY $65,000 EXTRA TO BUILD COMPARED TO A CONVENTIONAL HOUSE.
My Net-Zero Energy HouseWhat were the design criteria?
Objectives of my Net-Zero Energy HouseObjectives of my Net-Zero Energy House
Sustainable Energy Design (uses no fossil fuels)Sustainable Energy Design (uses no fossil fuels)Generate as much energy ‘on site’ in a year as Generate as much energy ‘on site’ in a year as is used on site in that year.is used on site in that year.Be energy efficientBe energy efficientBe cost-effectiveBe cost-effectiveBurn NO fuel of any kind on site IF POSSIBLEBurn NO fuel of any kind on site IF POSSIBLEUse sustainable materialsUse sustainable materialsUse materials with low toxicityUse materials with low toxicityCost should be competitive with conventional Cost should be competitive with conventional home over a 20-year period, i.e., if you pay more home over a 20-year period, i.e., if you pay more to build it then savings from operating costs to to build it then savings from operating costs to pay for it should break even in the first 20 years.pay for it should break even in the first 20 years.
Cost-effective ConsiderationsCost-effective ConsiderationsWhich costs more?Which costs more?
Insulating the house?Insulating the house?
Providing sun & wind power systems?Providing sun & wind power systems?
Cost-effective ConsiderationsCost-effective ConsiderationsWhich costs more?Which costs more?
Insulating the house?Insulating the house?
Providing sun & wind power systems?Providing sun & wind power systems?
To answer these questions we first needto know how much energy a typical house uses in a year.
Cost-effective ConsiderationsCost-effective ConsiderationsWhich costs more?Which costs more?
Insulating the house?Insulating the house?
Providing sun & wind power systems?Providing sun & wind power systems?
To answer these questions we first needto know how much energy a typical house uses in a year.
Where does most of my energy go?• To general electrical needs?• To heating?
Energy Audit of my HouseEnergy Audit of my House
Lights and electrical appliances?Lights and electrical appliances?
Hot water needs?Hot water needs?
Heating in winter months?Heating in winter months?
Need to use common units!Need to use common units!J = Joules or GJ = Giga JoulesJ = Joules or GJ = Giga Joules
kWh = kilowatt hours = 3,600,000kWh = kilowatt hours = 3,600,000 JJBTU = British Thermal UnitsBTU = British Thermal Units
(1 kWh = 3,412 BTU)(1 kWh = 3,412 BTU)
Approximate Energy AuditApproximate Energy Audit
Energy Consumption Per YearEnergy Consumption Per Year 9,000 kWh lights, appliances etc9,000 kWh lights, appliances etc
4,500 kWh hot water4,500 kWh hot water
35,000 kWh heating 35,000 kWh heating (assumes 90% burn efficiency)(assumes 90% burn efficiency)
Total: 48,500 kWhTotal: 48,500 kWh18.5% lights, appliances etc18.5% lights, appliances etc
9.3% hot water9.3% hot water
72.2% heating72.2% heating
Lights & Appliances: 18.5%Lights & Appliances: 18.5%How to save energy?How to save energy?
Compact fluorescent lighting VERY cost Compact fluorescent lighting VERY cost effectiveeffectiveSelect washing machine with high spin Select washing machine with high spin cyclecycleDry clothes outside on line (free) rather Dry clothes outside on line (free) rather than in drier as much as possiblethan in drier as much as possibleSelect energy efficient dish washerSelect energy efficient dish washerUse microwave rather than stove as much Use microwave rather than stove as much as possible.as possible.
Domestic Hot Water: 9.7%Domestic Hot Water: 9.7%How to save Energy?How to save Energy?
Use heat pump to boost heating efficiency up Use heat pump to boost heating efficiency up to 300%.to 300%.Add insulation to your hot water tankAdd insulation to your hot water tankLower the thermostat temperature on hot water Lower the thermostat temperature on hot water tanktankUse less hot waterUse less hot water
1.1. Install low-flow shower headsInstall low-flow shower heads2.2. Take quicker showersTake quicker showers3.3. Wash all clothes in cold waterWash all clothes in cold water4.4. Select dish washer that uses less waterSelect dish washer that uses less water
Heating of your home: 72.2%!!Heating of your home: 72.2%!!How to save energy?How to save energy?
Biggest potential saving!Biggest potential saving!
Needs energy audit of your home!Needs energy audit of your home!
Where does my heat go? Considerations are:Where does my heat go? Considerations are:
1.1. Heat loss through walls & roofHeat loss through walls & roof
2.2. Heat loss through windowsHeat loss through windows
3.3. Heat loss to provide fresh air in winterHeat loss to provide fresh air in winter
4.4. Efficiency of your furnaceEfficiency of your furnace
5.5. Cost of your fuel (for cost-effective solutions)Cost of your fuel (for cost-effective solutions)
Insulation efficiency determined by Insulation efficiency determined by R-values of ceiling, walls, windowsR-values of ceiling, walls, windows
Typical values for modern homesTypical values for modern homes
Windows R = 2.8 to 3.3Windows R = 2.8 to 3.3
Walls R = 18 to 22Walls R = 18 to 22
Ceiling R = 30 to 35Ceiling R = 30 to 35
Bigger R values are betterBigger R values are better
But heat loss for each item determined by But heat loss for each item determined by
BTU/h = (Sq ft surface area/R)*(TBTU/h = (Sq ft surface area/R)*(T inin-T-Toutout))
How I learned to do the calculations!How I learned to do the calculations!The Passive Solar House by James KachadorianThe Passive Solar House by James Kachadorian
Approximate Energy Audit of a home Approximate Energy Audit of a home NEEDS A PLAN for computationsNEEDS A PLAN for computations
Approximate Energy Audit of Approximate Energy Audit of modern home.modern home.
TOTAL heat loss rate 550 BTU per h per TOTAL heat loss rate 550 BTU per h per ooFF
13.5% thru windows13.5% thru windows
13.6% thru walls13.6% thru walls
8.7% thru roof8.7% thru roof
15.7% thru basement 15.7% thru basement OVER ESTIMATE!OVER ESTIMATE!
49.1% 49.1% TO PROVIDE FRESH AIRTO PROVIDE FRESH AIR
(16 room volume exchanges per day (16 room volume exchanges per day recommended by building code)recommended by building code)
Summary Energy ‘costs’Summary Energy ‘costs’to run my new hometo run my new home
48,500 kWh/yr (72% of this for heat)48,500 kWh/yr (72% of this for heat)
How much can I generate from a wind How much can I generate from a wind turbine and PV system purchased under turbine and PV system purchased under NYSERDA incentives?NYSERDA incentives?
www.powernaturally.orgwww.powernaturally.org
Use above web site for info on NY State Cash Use above web site for info on NY State Cash Incentives from NYSERDAIncentives from NYSERDAMr. Sal Graven, NYSERDA, informed me that as of Mr. Sal Graven, NYSERDA, informed me that as of Feb 2008Feb 2008
1.1. 28 Residential wind turbines have been installed 28 Residential wind turbines have been installed 2.2. 13 more wind turbines are scheduled under the 13 more wind turbines are scheduled under the
NYSERDA incentive programNYSERDA incentive program3.3. 900 Photovoltaic residential systems have been 900 Photovoltaic residential systems have been
installedinstalled4.4. My home is the first (and only) in NY State to provide My home is the first (and only) in NY State to provide
all power needs from the sun and wind under the all power needs from the sun and wind under the NYSERDA program. NYSERDA program.
NYSERDA INCENTIVES SUMMARYNYSERDA INCENTIVES SUMMARY
System Net Price System Est. An. Investment
type after rebates size Production per kWh
per yearper year
Turbine $24,850 10 kW 10,500 kWh $2.36
PV $35,000 10 kW 9,500 kWh $3.69
PV price includes battery back up system ($8,000)
Total Estimated Annual Production20,000 kWh
Closing the gapClosing the gapEnergy needs: 48,500 kWhEnergy needs: 48,500 kWh
Energy production: 20,000 kWhEnergy production: 20,000 kWh
Possible solutions include:Possible solutions include:
Use Passive Solar heatingUse Passive Solar heating
Use Active Solar for hot waterUse Active Solar for hot water
Use Active Solar heating for houseUse Active Solar heating for house
Decrease energy needs thru insulationDecrease energy needs thru insulation
Increase efficiency of heating Increase efficiency of heating
Problem with active or passive solar in the Problem with active or passive solar in the North Country: Very little sunshine in winterNorth Country: Very little sunshine in winter
AND systems are expensiveAND systems are expensive
MonthMonth Heating Deg DaysHeating Deg Days % sunshine% sunshine
OctoberOctober 542542 4343
NovemberNovember 896896 2525
DecemberDecember 13411341 2424
JanuaryJanuary 14711471 2424
FebruaryFebruary 12831283 3434
MarchMarch 10911091 4343
AprilApril 615615 4747
MayMay 317317 5353
Option of Adding Insulation?Option of Adding Insulation?
A complete analysis is beyond the scope of this A complete analysis is beyond the scope of this workshop (takes too long) but I consulted a workshop (takes too long) but I consulted a Green Builder in the Adirondacks who said he Green Builder in the Adirondacks who said he could reduce my heat load by 40% thru better could reduce my heat load by 40% thru better insulation etc at 20% extra cost.insulation etc at 20% extra cost.
Saving on heat load: 13,500 kWhSaving on heat load: 13,500 kWh
Added cost to construction: $44,000Added cost to construction: $44,000
Cost per kWh saved: $3.26Cost per kWh saved: $3.26
Remaining load: 48,500-13,500 = 35,000 kWhRemaining load: 48,500-13,500 = 35,000 kWh
Shortfall on project: 15,000 kWhShortfall on project: 15,000 kWh
Ultimate Cost-Effective Solution Ultimate Cost-Effective Solution used in my home.used in my home.
Biggest heating load (49%) is to provide Biggest heating load (49%) is to provide fresh airfresh air
Solution: Install fresh-air heat recovery Solution: Install fresh-air heat recovery systemsystem
Reduce energy cost to heat my homeReduce energy cost to heat my home
Solution: Install Geothermal Heat Pump Solution: Install Geothermal Heat Pump which provides 330% efficiency!which provides 330% efficiency!
Heat Recovery SystemHeat Recovery SystemCost: $2500 (installed)Cost: $2500 (installed)
Savings on heat load: 8,000 kWhSavings on heat load: 8,000 kWh
Cost per kWh saved: $0.31Cost per kWh saved: $0.31
Geothermal Heat PumpCost: $7,500 (installed)Cost: $7,500 (installed)
Savings on heat load: 20,000 kWhSavings on heat load: 20,000 kWh
(because of 330% efficiency)(because of 330% efficiency)
Cost per kWh saved: $0.38Cost per kWh saved: $0.38
Air-heat recovery systemAir-heat recovery system
70% heat recovery on air that passes thru system
Geothermal Heat PumpGeothermal Heat Pump
Explaining how it works needs workshop of its own!So details beyond the scope of my talk.
Types of Geothermal Heat PumpsTypes of Geothermal Heat Pumps
Open loop: most efficient (400%) but Open loop: most efficient (400%) but usually more expensive to installusually more expensive to install
Closed loop: less efficient (300%)Closed loop: less efficient (300%)
PLUS the heat pump assists the hot water PLUS the heat pump assists the hot water tank and hence reduces the energy tank and hence reduces the energy needed to heat hot water with electricity.needed to heat hot water with electricity.
Explain how it works (it is a very large Explain how it works (it is a very large refrigeration system)refrigeration system)
Cost & Payback AnalysisCost & Payback Analysis
y = 5.7643x - 4.6466
R2 = 0.9316
0.90
1.40
1.90
2.40
2.90
3.40
0.90 1.00 1.10 1.20 1.30 1.40
Electrical power price relative to 1999
oil
pri
ce
re
lati
ve
to
19
99
Rel price increase Linear (Rel price increase)
In past 9 years (basis 1999)NYSERDA data shows
Electrical price inflation: 3.7%Fuel Oil price inflation: 14.6%
Cost & Payback AnalysisCost & Payback AnalysisThis analysis uses conservative estimates of energy inflation ratesThis analysis uses conservative estimates of energy inflation rates
($80,000)
($60,000)
($40,000)
($20,000)
$0
$20,000
$40,000
$60,000
$80,000
$100,000
$120,000
2005 2010 2015 2020 2025 2030
Year
Cas
h f
low
3.6%+12.5% 3.6% inflation
20 year cash flow analysis 2007-2027
Electrical inflation: 3.7% Fuel oil inflation: 14.6% in last 9 years
Break-even system pays for itself
Final building costsFinal building costs
House with one-car garage: $220,000House with one-car garage: $220,000
Barn (one-car parking + shop): $35,000Barn (one-car parking + shop): $35,000
Sun & Wind Energy systems: $60,000Sun & Wind Energy systems: $60,000
Extra cost of Geothermal: $5,500Extra cost of Geothermal: $5,500
Price premium for Net-ZeroPrice premium for Net-Zero
Energy House vs conventional: 27% Energy House vs conventional: 27%
more than conventional home. more than conventional home.
Construction sequence Construction sequence illustrated by photos and wordsillustrated by photos and words
1.1. Built turbine in 2004/05Built turbine in 2004/05
2.2. Built barn in 2005Built barn in 2005
3.3. Added photovoltaic system in 2006Added photovoltaic system in 2006
4.4. Built house in 2007Built house in 2007
My Net-Zero Energy HouseSo, did I succeed? What are the measured
data on production and heat pump performance?
ProductionProduction
Production. The solar and wind systems Production. The solar and wind systems have been grid-tied for > 12 months. have been grid-tied for > 12 months. Production from 1 Dec 06 to 1 Dec 07: Production from 1 Dec 06 to 1 Dec 07: 19,005 kWh19,005 kWh
GHP = 7500 kWh GHP = 7500 kWh
HW = 4500 (will lower this in future) HW = 4500 (will lower this in future)
All other = 6000 kWh All other = 6000 kWh
TOTAL = 18,000 kWh TOTAL = 18,000 kWh
NZEH IN NZE-CITIESNZEH IN NZE-CITIESAdvantages for the future:Advantages for the future:
Sunlight is free & delivery is freeSunlight is free & delivery is freeCost to utilize free sun-energy will Cost to utilize free sun-energy will eventually be less than cost of fueleventually be less than cost of fuelWill reduce Canada carbon-footprintWill reduce Canada carbon-footprintWill conserve declining fossil fuels for Will conserve declining fossil fuels for more vital needsmore vital needsWill reduce size of electrical grid and avoid Will reduce size of electrical grid and avoid cost of new power plants (nuclear & cost of new power plants (nuclear & conventional)conventional)
NZEHNZEHImpact on how cities will look?Impact on how cities will look?
Street layout for S orientation of all housesStreet layout for S orientation of all houses
Modified look of housingModified look of housing
Modified landscaping (e.g., smaller trees, fewer Modified landscaping (e.g., smaller trees, fewer trees, or mostly deciduous trees??)trees, or mostly deciduous trees??)
Use of local materialsUse of local materials
Use of low toxicity materialsUse of low toxicity materials
Living roofs? Gray-water use? Rain water Living roofs? Gray-water use? Rain water storage?storage?
Unlimited possibilities for a sustainable future!Unlimited possibilities for a sustainable future!
Questions & DiscussionQuestions & Discussion
Heat Pump Consumption?Heat Pump Consumption?Data for 22 days in Jan 08Data for 22 days in Jan 08
RESULTS:RESULTS:792 = kWh power consumption of HP792 = kWh power consumption of HP160 = kWh power consumption of water pump160 = kWh power consumption of water pump942 = total kWh to heat the house.942 = total kWh to heat the house.1013 = HDD for the same 22 days in Dannemora, NY, 1013 = HDD for the same 22 days in Dannemora, NY, 1/8 of an average heating season already!1/8 of an average heating season already!0.93 = kWh/HDD = 942/1013 (This value has been 0.93 = kWh/HDD = 942/1013 (This value has been constant for the whole period, i.e., on cold days the constant for the whole period, i.e., on cold days the value is the same as on warm days)value is the same as on warm days)7448 = estimated kWh for an average heating season 7448 = estimated kWh for an average heating season = 0.93x8010= 0.93x8010$1191 = estimated cost of heating with electricity @ $1191 = estimated cost of heating with electricity @ 16cents/kWh.16cents/kWh.
Heat Pump EfficiencyHeat Pump EfficiencyDefinition: 1 BTU Definition: 1 BTU = amount of heat energy required to = amount of heat energy required to change 1 lb of water 1 change 1 lb of water 1 ooFFHeat Extraction rate (HE) from well water in BTU/hrHeat Extraction rate (HE) from well water in BTU/hr( 1 Gal water = 8.35 lbs. 60 min per hr. So if you pump ( 1 Gal water = 8.35 lbs. 60 min per hr. So if you pump water at 1 GPM you are pumping about 500 lb water per water at 1 GPM you are pumping about 500 lb water per h)h)HE = 500 x GPM x (drop in Water temperature) in HE = 500 x GPM x (drop in Water temperature) in BTU/hrBTU/hrTypical performance values of my HP: Typical performance values of my HP: For Stage 1 Heating: GPM = 9.5 & temp drop = 7 oF, For Stage 1 Heating: GPM = 9.5 & temp drop = 7 oF, hencehence HE = 500 x 9.5 x 7 = 33,250 BTU/hrHE = 500 x 9.5 x 7 = 33,250 BTU/hrFor Stage 2 Heating: GPM = 9.5 & temp drop = 10 oF, For Stage 2 Heating: GPM = 9.5 & temp drop = 10 oF, hencehence HE = 500 x 9.5 x 10 = 47,500 BTU/hrHE = 500 x 9.5 x 10 = 47,500 BTU/hr
Heat Pump EfficiencyHeat Pump EfficiencyHeat Supply rate (HS) to house in BTU/hrHeat Supply rate (HS) to house in BTU/hrHS = 1.06 x Air Flow Rate (CFM) x (temperature rise HS = 1.06 x Air Flow Rate (CFM) x (temperature rise of air of air OOF)F)Measured temp rise of air is 28 to 31 Measured temp rise of air is 28 to 31 ooF F CFM counter LED indicates CFM rates of 800, 1100, CFM counter LED indicates CFM rates of 800, 1100, 1500 or 1800 while system operates. 1.06x28x1500 = 1500 or 1800 while system operates. 1.06x28x1500 = 44,500 1.06x31x1800 = 59,150)44,500 1.06x31x1800 = 59,150)Start up sequence: CFM 800 Start up sequence: CFM 800 Stage 1 Stage 1 1100 @ 75F 1100 @ 75F 1500 @ 90 F 1500 @ 90 F Heat off 800. Heat off 800.
ALTERNATIVE CALCULATIONALTERNATIVE CALCULATIONHS = HE +EA, where EA = energy added by my HS = HE +EA, where EA = energy added by my compressor & fancompressor & fan
Typical performance of my heat pump:Typical performance of my heat pump: For Stage 1 Heating : EA = 3.0 kW = 10,230 BTU/hr HS For Stage 1 Heating : EA = 3.0 kW = 10,230 BTU/hr HS = 43,480 (rated 41,650)= 43,480 (rated 41,650) For Stage 2 Heating: EA = 4.26 kW = 14,500 BTU/hr HS For Stage 2 Heating: EA = 4.26 kW = 14,500 BTU/hr HS = 62,000 (rated 59,450)= 62,000 (rated 59,450)
( 1 kW = 3,410 BTU/hr)( 1 kW = 3,410 BTU/hr)
Heat Pump EfficiencyHeat Pump Efficiency
Efficiency estimate (needs data on water pump)Efficiency estimate (needs data on water pump) Energy required to pump water = 6.8 A x 220 V Energy required to pump water = 6.8 A x 220 V x 50% duty cycle = 0.75 kWx 50% duty cycle = 0.75 kW = 2,600 BTU/hr= 2,600 BTU/hr
For Stage 1 Heating: For Stage 1 Heating: COP = 43,480/10,230 = 4.25 COP = 43,480/10,230 = 4.25 Efficiency = 43,480/(10,230+2,600) = 339%Efficiency = 43,480/(10,230+2,600) = 339%
For Stage 2 Heating: For Stage 2 Heating: COP = 62,000/14,500 = 4.27COP = 62,000/14,500 = 4.27 Efficiency = 62,000/(14,500+2,600) = 363%Efficiency = 62,000/(14,500+2,600) = 363%
www.powernaturally.org
SWIEPSWIEPSmall Wind Information Exchange ProgramSmall Wind Information Exchange Program
http://www.ualberta.ca/~mtyree/SWIEP/
Items for discussion?Items for discussion?Relative cost of Energy per unit energy
NYSERDA data from 2006
0.00 0.50 1.00 1.50 2.00 2.50 3.00
Electrical
Propane
Kerosene
Fuel Oil
Nat. Gas
Coal NYSERDA NYSERDA $/millionBTU$/millionBTU
$5.51$5.51 CoalCoal
$15.49$15.49 Nat. GasNat. Gas
$18.65$18.65 Fuel OilFuel Oil
$21.23$21.23 KeroseneKerosene
$26.06$26.06 PropanePropane
$48.92$48.92 ElectricityElectricity