Objectives

• Analysis tools for determining cost and cost-effectiveness

Cost energy efficiency and renewables

• What is the appropriate cost of energy?• Huge variation nationally• Depends on customer• Depends on sector• Energy• Transmission• Distribution• Fuel

How much do you pay for electricity?

• 0.0177 $/kWh

• 0.0355 $/kWh

• 0.0532 $/kWh

• 0.1169 $/kWh

• Depends on how much I use

• Depends on what time of year

Rate (E01):

WinterBilling Months

November through April

SummerBilling Months

May through October

Customer Charge

$6.00 $6.00

Energy Rate (E01)

3.55¢ per kWh, first 500 kWh

3.55¢ per kWh, first 500 kWh

 6.02¢ per kWh, for all

kWh over 500 kWh7.82¢ per kWh, over 500

kWh

Fuel Adjustment Clause (FAC) - plus an adjustment for variable costs, calculated according to the Fuel Adjustment Clause Tariff, multiplied by all kWh.

Primary Service

(For Rates: E01, E02, E03, E04, E05, E06, E10, E13, E14, E23, ENW)

January 1999 - July 2000 $ 0.01372

August 2000 - October 2000 $ 0.01635

November 2000 - January 2001 $ 0.02211

February 2001 - December 2001 $ 0.02682

January 2002 - June 2003 $ 0.01774

July 2003 - October 2003 $ 0.02004

November 1, 2003 - December 31, 2003 $ 0.02265

For electric bills received beginning January 1, 2004

$ 0.02796

   

Which state has the highest residential electricity rate?

• What determines this?

• Why are there large discrepancies?

• What are differences between utilities?

• What is deregulation?

Electricity Restructuring (Feb. 2003)

http://www.eia.doe.gov/cneaf/electricity/chg_str/regmap.html (Feb. 2003)

What should you pay for electricity?

http://www.eia.doe.gov/cneaf/electricity/page/fact_sheets/retailprice.html

What should you pay for electricity?

• Is electricity cheaper or more expensive in Austin than in the rest of the world?

• 2002 numbers• Nuclear ($0.10/kWh)• Gas ($0.03/kWh)• Coal ($0.05/kWh)

What about natural gas?

• How is natural gas sold?

• What does it cost?

• http://www.eia.doe.gov/pub/oil_gas/natural_gas/data_publications/natural_gas_monthly/current/pdf/table_21.pdf

• ~1000 BTU/ft3

• ft3 = cf, ccf = 100 ccf = 1therm

What does gas cost in Austin?

• Austin $0.78/ccf (March 2003)

• Austin $1.82/ccf (March 2004) or $0.24/ccf

• Gas prices rose 43% February to March 2003

• Gas market is heavily influenced by electricity market

• Gas market is more subject to manipulation

Question 1

• How much cheaper is it to heat with a gas furnace than a electric resistance furnace?

• Other issues• Fan (adds heat at electricity rate)• Pilot light (0.2 therm/day)• Safety• Equipment cost• Maintenance

Austin Energy Code Requirements

Glazing percent of gross wall area: 15% 18% 20% 25%

Exterior walls R-13 R-13 R-13 R-13

Floors over unconditioned space R-11 R-11 R-11 R-13

Attics and knee walls R-26 R-30 R-30 R-30

Glazing U-factor (max) 0.75 0.65 0.60 0.52

Question 2

• What is the cost/benefit of insulating my house with R-19 instead of R-13?

• 1150 ft2 of wall area

• 0.76 $/ft2 for R-13

• 1.70 $/ft2 for R-19

• How much does the answer change if I had gas heat?

Question 2 Issues

• How do we figure out how much heat I need?

• Weather data (what is relevant data?)

• Bill analysis (statistics)

• Modeling/simulation

Question 3

• ECJ 9.236 delamp from four 40W fluorescent tubes to two 34W tubes• Cost/fixture is $100• Assume constant ballast factor

• What is cost/benefit?

Question 3 issues

• What is cost of electricity?• http://www.austinenergy.com/rates/large-primary.

html

• How do you figure out savings from reduced cooling?

• How long are lights on?

• What other costs are important?

Question 4

• How much does sealing and/or insulating heating and cooling ducts save?

• Cost varies considerably

• ~Small homes, $350/home

• We are interested in the system efficiency• Overall impact of ducts

Duct System efficiency

Site T08, Eugene OR

• Efficiency went from ~ 40% to around 80%

• Electric resistance furnace

• Electricity was $0.05/kWh

• How would we figure out how much we would save?

Efficiency program evaluation

• Apply savings from a particular measure to a large number of buildings

• Assume statistical averages for population and building evaluation

• Can be significant deviation• Almost always overpredict savings

• Need to measure savings

Reminder: Cost of renewables

Fuel Cost US¢/kWh

Solar 30

Wave 9

Biomass 6

Wind 5

How much does conservation cost?

• Who is paying for it?• How long does a measure last?• What else can you do with the money?• How valuable is reducing pollution?• What common myths are out there?

• For duct sealing project shown above – cost was about 0.005 $/kWh

Savings

• Costs and benefits are tractable• Often not obvious• Require analysis and consideration of factors

removed from actual issue• Consider non-economic benefits

• LEED• Cost per point debate