Power Supply & Demand, presentation given by Tony Ramunno, Director, Engineering & Project Management for Great River Energy. Presented at the February 18, 2010 Maximize Minnesota event held at South Central College, North Mankato, MN

1. Power Supply & Demand Tony Ramunno Director, Engineering & Project Management Great River Energy

2. Great River Energy G&T Cooperative 28 Member Cooperatives Customer Interface 634,000 Members (Owners) Sales: 57.4% Residential 40.2% Commercial and Industrial, Agriculture 2.4% Seasonal 5th largest G&T in nation Second largest utility in Minnesota Tony Ramunno - Director Engineering & Project Management - Transmission

3. Great River Energy Service area covers 60% of Minnesota Nearly 850 employees (in MN and ND) 2,800 MW of generation 4,500 miles of transmission lines Total assets: $2.3 billion

4. Overview of Presentation Generation types/cost/application Power Delivery – Transmission Correlation of load to electrical infrastructure What can we do!

5. Introduction Electricity Is not Magic Can’t be stored/warehoused Ordered, Manufactured, and delivered “on-demand” Electricity usage and production costs are directly related! Infrastructure must be built to accommodate “peak demand” Assets are expensive ($$ and lead time) Users of electricity share the cost

6. Power Generation The Lowest Cost Plant is the one not built!

7. Matching Generation & Load Types Unpredictable or added to high Load timeframe High Cost Generation Cycling, Seasonal, other predictable Load ContinuousLoad Low Cost Generation

8. Power Delivery System OverviewTransmission Must Cover “peak load” Generating Plants Purchased Power Power is generated or purchased Bulk transmission (DC line and >115kv) moves the power to transmission substations, allows reserve sharing, and integrates resources into a regional grid Bulk Transmission Bulk Transmission Substation These substations drop the voltage down Load serving transmission (<115kv) moves the power to distribution substations Load Serving Transmission distribution substations drop the voltage down Distribution Substations Distribution Lines distribution lines move the power to the end customer.

9. Typical Utility Demand Curve

10. Ideal Load Curve!

11. What Can We Do! Understand/manage process energy usage Energize/de-energize frequency/duration Staging starts/stops to levelize load Consider energy in utilization equation Is there operational flexibility? Can facility load be shifted to off-peak times? Consider energy in equipment selection Energy efficiency – upfront vs. lifetime costs

12. Working Together Collaborate with Electric Utility Time of day or time of year load benefits On-site emergency generation capabilities Load shedding or other flexibility during times of emergency We all share the costs for Electrical Infrastructure! We all share the savings of deferred/delayed infrastructure!

13. Questions