Co-generation Cogeneration is an attractive option for facilities with high electric rates and buildings that consume large amounts of hot water and electricity.

Co-generation

• Cogeneration is an attractive option for facilities with high electric rates and buildings that consume large amounts of hot water and electricity every month. The higher the electric rate; the greater the savings.

Last 3 years of Utility Costs at BHS

310000

320000

330000

340000

350000

360000

370000

380000

390000

400000

410000

1

BHS Utilities CostComparison

2003-2004

2004-2005

2005-2006

Tri-Generation• A tri-generation system produces

electricity and utilizes the waste heat to produce heating in the winter.

• With the addition of an absorption/bromine chiller this system will also provide cooling for the building.

22’

23’

Site ~ 22’* x 23’Service ~ 30’ x 28’

PRE-ENGINEERED LAYOUTS

Site ~ 22’* x 29’Service ~ 30’ x 34’

Site ~ 22’* x 29’Service ~ 30’ x 34’

22’

29’

• System = 28,550 lbs • System = 30,833 lbs • System = 32,566 lbs

29’

System Height = 15’6”

22’

240 kW 300 kW 360 kW

Benefits

• Environmentally friendly• Reduces fossil fuel consumption• Reduces dependency on electrical grid• Produces electricity while also providing

heating or cooling as a by-product• Provides backup generation capabilities• Extends life of existing equipment• Saves Money $$$$$$$$$$$$$$$$$$$$

2,089

1,753

1,2371,131 1,128

Coal Petroleum Gas PureComfort PureCell

US Fossil Fueled Grid Average = 1969

570

2,089

1,753

1,2371,131 1,128

Coal Petroleum Gas PureComfort PureCell

US Fossil Fueled Grid Average = 1969

570

Ref: US DOE EIA (Electricity Generation & Environmental Externalities, 1995)

Environmental BenefitsGreenhouse Gas Reduction (lbm/MWh)

Avoided emissions

Coal 50%

Oil 20%

Natural gas 30%

Waste heat

Electricity

100%

33%

67%

Low efficiency – Significant amount of energy is lost to the atmosphere as waste heat

Source: Adapted from U.S. Combined Heat and Power Association

More pollution released

Higher costs to Branford BOE

Grid Power

Risks

• Energy costs decrease (Electricity)

• Natural Gas rises/Oil prices fall

• Equipment Failure (Maintenance and replacement costs are built into agreement and calculated into savings)

Energy Rates - Snapshots

http://www.clpenergyinfo.com/stabilize/index.php

http://www.wtrg.com/daily/heatingoilprice.html http://www.wtrg.com/daily/gasprice.html

Costs Associated

• Purchase of Natural Gas

• BOE would seek long term contract on Natural Gas

• Initial Equipment Purchases

• Equipment maintenance

Incentives

• DPUC Grants/Rebates $500.00 per KW or approx $120,000

• Additional grants• Positive cash flow in first year• Increased cash flow in subsequent years • No-upfront costs• Environmental benefits• No gas distribution charges

Natural gas

Waste heat

Electricity

Hot water

Chilled water100%

80%

High efficiency – More waste heat recovered and converted to usable energy

Source: Adapted from U.S. Combined Heat and Power Association

20%

Less pollution released

Lower costs and assured power to the end user

or

Financial Model

Energy Savings Assumptions:Electrical Power 8,322 Hours Generated

Cooling 2,628 HoursHeating 3,504 Hours

Aux. Thermal Heating 1752 HoursBaseline Electrical Rate 16.70 ¢/kWh

Baseline Natural Gas Rate 9.50$ /MCFBaseline Fuel Oil Rate 2.40$ /gallon

PurchaseCapital Cost 1,029,790$ Incentive or Rebate 120,000$ Net Purchase Price 909,790$

4.4

Year 1 2 3 4 5 6 7 8 9 10 TotalPurchase Payment (909,790)$ (909,790)$ Annual Energy Savings 207,124$ 215,409$ 224,025$ 232,986$ 242,306$ 251,998$ 262,078$ 272,561$ 283,463$ 294,802$ 2,486,753$ Annual Maintence Cost (49,660)$ (51,398)$ (53,197)$ (55,059)$ (56,986)$ (58,981)$ (61,045)$ (63,181)$ (65,393)$ (67,681)$ (582,581)$ Overhaul Cost -$ -$ -$ -$ Annual Positive Cash Flow (Cumulative) (752,326)$ 164,011$ 170,828$ 177,927$ 185,320$ 193,018$ 201,033$ 209,380$ 218,071$ 227,121$ 994,382$

Net Present Value $649,478 @ 4.0%

Capital LeaseCapital Cost 1,029,790$ Incentive or Rebate 120,000$ Net Purchase Price 909,790$

Rate 5.9% annualTerm 10 years

Year 1 2 3 4 5 6 7 8 9 10 TotalAnnual Lease Payment (116,172)$ (116,172)$ (116,172)$ (116,172)$ (116,172)$ (116,172)$ (116,172)$ (116,172)$ (116,172)$ (116,172)$ (1,161,722)$ Annual Energy Savings 207,124$ 215,409$ 224,025$ 232,986$ 242,306$ 251,998$ 262,078$ 272,561$ 283,463$ 294,802$ 2,486,753$ Annual Maintenance Cost (49,660)$ (51,398)$ (53,197)$ (55,059)$ (56,986)$ (58,981)$ (61,045)$ (63,181)$ (65,393)$ (67,681)$ (582,581)$ Overhaul Cost -$ -$ -$ -$ -$ -$ -$ -$ -$ -$ -$ Annual Positive Cash Flow 41,292$ 47,839$ 54,656$ 61,755$ 69,148$ 76,845$ 84,861$ 93,207$ 101,899$ 110,948$ 742,450$

157,464$ 164,011$ 170,828$ 177,927$ 185,320$ 193,018$ 201,033$ 209,380$ 218,071$ 227,121$ AssumptionsAnnual Energy Escalation 4.0%Annual Maintenance Escalation 3.50%

Heating fuel Savings WIS

• Walsh Intermediate HVAC replacement project 2003-2004

• Annual reduction of 60,000 gallons #2 Heating Fuel Oil• The 02-03 heating season used 98,034 gallons of fuel• 03-04, 38,454 gallons used• 04-05, 35,117 gallons used• 05-06, 29,733 gallons used• 06-07, 35,644 gallons used• Fuel Avoidance since project completion 253,188

Gallons or

WIS HVAC  WIS Baseline   Did Nothing WIS Actual   Did Nothing WIS Actual

Utilities 2001/2002   2004/2005 2004/2005   2005/2006 2005/2006

Oil Gallons 98,454.00   98,454.00 35,117.00   98,454.00 29,733.00

Oil Cost Total $85,654.98   $172,294.50 $61,454.75   $201,830.70 $60,952.65

Cost per gallon 0.87   1.75 1.75   2.05 2.05

Electric KWH 2,780,160   2,780,160 1,431,360   2,780,160 1,448,640

Electric Cost $247,933.00   $344,739.84 $178,202.00   $378,101.76 $198,129.00

Electric Rate 0.089   0.124 0.124   0.136 0.136

Totals $333,587.98   $517,034.34 $239,656.75   $579,932.46 $259,081.65

Cost Avoidance       $277,377.59     $320,850.81

Capital Lease $1,209,840.00     $120,984.00     $120,984.00

WIS Electrical Costs despite annual inflation

$0.00

$50,000.00

$100,000.00

$150,000.00

$200,000.00

$250,000.00

$300,000.00

01-02 02-03 03-04 04-05

Series1

Other conservation initiatives

CT Municipal Lighting Grants all buildings

• 2004-2005 The BOE took advantage of the CT Municipal Lighting Grants to install energy efficient lighting in all of our buildings at no cost to the town of Branford.

• As a result annually we are saving 406,849 Kwh or in today’s cost $72,826.00 annually.

EMS at MTM and MRT

• Cost of Project is $43,000.00 per school

• Completed Project November 17, 2006

Most Recent Energy Project

• Installation of EMS (Energy Management System) at Murphy and Tisko Elementary Schools completed Fall 2006

• Involves building scheduling, outside air calibration to equipment operation, 365 day calendar scheduling, soft starts for equipment, internet and intranet monitoring of temperature and operational conditions in schools

MTM/MRT Energy Savings

• 2005/2006 Fuel Use 36,251 gallons

• 2006/2007 Fuel Use 17,869 gallons

• Fuel Avoidance 18,382 Gallons

• Cost Avoidance $35,185 in 06/07 dollars

• Although the fiscal year for electricity is not complete we are on track to save 10-15% or approx 72,500 kwh or $12,000.00

• Simple Payback of less than two years

Summary

• We have made strides in reducing our energy consumption and holding the line on our energy costs.

• Next steps toward conservation are much more involved but necessary if we are to operate our schools in an environmentally friendly and economical manner.

• We are seeking opportunities and assistance in continuing our conservation program