Solar Energy:Location Is Everything?

Scott PetersonScott Peterson

Environmental Engineering Texas A&MEnvironmental Engineering Texas A&M

Increasing population and decreasing fossil fuel reserves Increasing population and decreasing fossil fuel reserves require that we change our energy system from its current require that we change our energy system from its current reliance on fossil fuels (80%)reliance on fossil fuels (80%)

The successor chosen should be a sustainable energy source The successor chosen should be a sustainable energy source Sustainable meansSustainable means

RenewableRenewable Environmentally FriendlyEnvironmentally Friendly

Solar power has the possibility to meet these requirementsSolar power has the possibility to meet these requirements

Energy Sources

Source: BP Statistical Review of World Energy 2003Source: BP Statistical Review of World Energy 2003

Energy Consumption

Source: BP Statistical Review of World Energy 2003Source: BP Statistical Review of World Energy 2003

Increasing Population

Source: Values for 1995-2050 for the low, medium, high and constant scenarios were obtained from World Population Prospects:The 1998 Revision, vol. I, Comprehensive Tables (United Nations, publication, Sales No. E.99.XIII.9). All other values are the result of the long-range projections.

Worldwide Energy Demand

Based on 1.5 ton oil equivalent per capita, Based on 1.5 ton oil equivalent per capita, 1.5-1.36 (1970s), and 1.5-1 respectively1.5-1.36 (1970s), and 1.5-1 respectively

400050006000700080009000

1000011000120001300014000

1970 1990 2010 2030 2050Year

Mill

ion

Ton

Oil

Equ

ival

ent

CO2 Emissions

Is Solar Power Feasible? In 2003 Texas Consumed 322,685,955 MWhoursIn 2003 Texas Consumed 322,685,955 MWhours It would take roughly 11kmx11km in 7.66kWhmIt would take roughly 11kmx11km in 7.66kWhm-2-2dd-1-1 solar solar

areaarea

What is CSP?

Parabolic Troughs Currently Best

Sunlight is concentrated on pipeSunlight is concentrated on pipe 150 MW Plant150 MW Plant

Placement

Unfortunately it isn’t this simpleUnfortunately it isn’t this simple We need to ConsiderWe need to Consider

Losses to ResistanceLosses to Resistance Stability (e.g. Volcanic Eruptions)Stability (e.g. Volcanic Eruptions) Existing InfrastructureExisting Infrastructure Where is the power needed?Where is the power needed?

Goals

Automate Process to a DegreeAutomate Process to a Degree Use Electricity Demand GIS DataUse Electricity Demand GIS Data Allow Users to Input TimeframeAllow Users to Input Timeframe Output Desirability MapOutput Desirability Map Enable the Process for Multiple Uses Enable the Process for Multiple Uses

(Solar, Wind, and so forth)(Solar, Wind, and so forth)

Case Study: Dallas

Geographic Data of Demand is very Geographic Data of Demand is very difficult to achievedifficult to achieve

Dallas Used to Test Different ConceptsDallas Used to Test Different Concepts

Initial Cost Allocation

Cost allocation via Cost allocation via transmission lines and transmission lines and arbitrary estimate for costs arbitrary estimate for costs of installing new High of installing new High Voltage linesVoltage lines

Cities are also included as Cities are also included as no new transmission line no new transmission line costcost

Resistance Depends on Length and AreaResistance Depends on Length and AreaPower inversely proportional to LengthPower inversely proportional to Length

High Voltages increase powerHigh Voltages increase power

Resistance of a Wire

Resistivity Has Great Affect

Shows maps of ideal Shows maps of ideal placement only focusing placement only focusing on different resistance/Lon different resistance/L

Vary the losses to Vary the losses to resistanceresistance

Time Cost Allocation

Must take into account the CSP efficiencyMust take into account the CSP efficiency kW/m2/day/($/m2)*days=kW/$ @ sourcekW/m2/day/($/m2)*days=kW/$ @ source Can be used to Calculate costCan be used to Calculate cost Plant life estimates for trough around 30yrsPlant life estimates for trough around 30yrs

Total Cost

Break Even: Initial + resistance losses=salesBreak Even: Initial + resistance losses=sales This depends on the electricity sales valueThis depends on the electricity sales value The value of electricity is increasingThe value of electricity is increasing Market uncertainty makes prediction Market uncertainty makes prediction

difficultdifficult

Other Ideas

Use Electricity Demand and Solar Use Electricity Demand and Solar Availability to create “Solar Shed” mapsAvailability to create “Solar Shed” maps

Then data tools designed for watersheds can Then data tools designed for watersheds can be usedbe used

Electricity Demand Data

Can be calculated on a per meter basis byCan be calculated on a per meter basis by

Is this accurate? No. In 2003 Electricity Breakdown wasIs this accurate? No. In 2003 Electricity Breakdown was

While these other distributions are not identical to population While these other distributions are not identical to population they are closethey are close

  Residential Commercial Industrial Total

MWh 121,354,826 96,694,234 104,546,895 322,685,955

Map of Electricity Demand

Difference at 0.001% Coverage

Conclusions

Our methods of providing power must Our methods of providing power must changechange

Solar Power placement is importantSolar Power placement is important Interesting: PV systems not economically Interesting: PV systems not economically

feasible, CSP systems almost are, However feasible, CSP systems almost are, However PV systems gaining market acceptance PV systems gaining market acceptance faster.faster.