Why Save Energy z Lower Overhead z Improve property value z Increase Rents z Decrease your environmental footprint.

Why Save Energy

Lower OverheadImprove property

valueIncrease RentsDecrease your

environmental footprint

Saving Energy and Using Solar Hot Water Systems

Richard Reis, PE301-325-8001www.conservationengineering.com

Sierra Club member since the 1960s

Energy Efficiency Problem

CoalPowerPlan

WasteHeat

LineLosses

Transmission LinesMotors

PumpLosses

Drive Train

Losses

ThrottleLosses

PipeLosses

Magnetic and

ResistiveLosses

UsableWork9.5%

Of CoalEnergy

*

* Carbon Dioxide (global warming gas)* Oxides of Sulfur and Nitrogen* Mercury compounds

From Destructive

Mining Practices

1. Determine Energy Demand

Begin by analyzing utility bills to determine How much energy you consume When you consume it How much of your utility costs are for base usage and how

much is for peak demand.

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Off Seasonal Average

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Community Pool

Food Wholesaler

2. Determine How Electricity is Used

ExampleData were taken from:Load nameplate readingsOperating timesActual usage not feasible

as pool was not in use during study period

Focus effort on top loads

3. Recommend Methods to Lower Energy Use

Identify opportunities to saveDetermine cost of installing

improvementsDetermine the benefit for each

changeIdentify the payback interval and / or

property value improvement.

4. Implement Energy Savings

SkylightsAvoid the need for

electric lights 75% of the time.

Natural lighting is more pleasant

More efficient LightsReduce energy useLast longerBetter color balance New Old

Solar Water Heating

Tried and true technology - has been used for decades

Far less costly than solar electric installations

Potential for significant governmental grants and tax benefits

Components of Solar Hot Water Heaters

Solar collectors on roofHeat exchangerHot water storage tankControllerPumpPipes and wiring to interconnect the

system

SchematicDiagram ofSystem With Data Logging

Reis, R.“Fine-Tuning a SolarWater-Heating System”,Solar Today, April 2009

http://solartoday.org/waterheating/

Investment Analysis Example for Solar Hot Water System

Total Investment Cost $11,383.00State Energy Grant $1,928.94Federal Tax Credit $4,808.00 (Not all realized for 2006)Net Cost $4,646.06

Baseline Energy Usage 880 kWh 2004-2005Average Current Energy Usage 300 kWh 2007Savings per month 580 kWh

Cost / kWh $0.17

Monthly Savings $98.60Months / year 12Annual Savings $1,183.20

Payback Interval 3.93 years

Small apartment house example

Payback intervals are about 4 times longer for solar electric.

Importance of Commissioning

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Issues Resolved

My early 80s Hot Water Solar System (still working)

Newer System usesantifreeze to prevent winter freezing. This older system is a drain back system. The solar Fluid is just water which drains back to the small heatexchanger tank when the sun is not shining.

Collectors

ConventionalHot Water

Tank

Hot WaterStorage

Tank

Heat Exchanger

Tank

Pumps