©2009. Northern Power Systems. All Rights Reserved. Not to be used or shared without permission. Proprietary and Confidential.

A New Isolated Grid Paradigm; All Renewables-----No Diesel Brett Pingree, VP America’s Northern Power Systems March 9 th, 2011

©2009. Northern Power Systems. All Rights Reserved. Not to be used or shared without permission. Proprietary and Confidential. Agenda Why No Diesel? Similarities to Isolated Arctic Grid Projects Overview of Project What Does the All RE Model Look Like? Project Details Challenges to Project

©2009. Northern Power Systems. All Rights Reserved. Not to be used or shared without permission. Proprietary and Confidential. Why No Diesel? Hedge Against Rising Costs (and Procurement) of Diesel Acquisition Limited Hazardous Waste Impact Reduced Acoustic Impact Save on Fuel Storage Costs Significantly Increase Safety Make a Green Statement (Marketing)

©2009. Northern Power Systems. All Rights Reserved. Not to be used or shared without permission. Proprietary and Confidential. Similarities to AK Isolated Grid Projects Expensive Diesel!! Difficult Access to Sites Cranes, Heavy Equipment, and Skilled Labor Weather (Hurricanes and Extreme Heat) Weak Grid, Intermittent Power Permitting and Fish/Wildlife (Iguanas and Parrots) Soil challenges (Coral) Salt Corrosion Sharks instead of Bears

©2009. Northern Power Systems. All Rights Reserved. Not to be used or shared without permission. Proprietary and Confidential. All Renewable Bahamian Resort 2 Parallel 300 kVA Static Power Invertors 5 Proven’s 15kW 2 Northern Power 100kw 4 PV arrays of 308 Panels (65kW dc) each [260 Kw total] 3 x 250kW Backup CAT Diesels 2.16 MW-Hr Battery Storage System 3 Battery Banks 360Vdc (180 cells (2000AHr) each) Associated DC and AC switching On-line June 2011 Expects to be the First 100% All Renewable Energy Destination Resort

©2009. Northern Power Systems. All Rights Reserved. Not to be used or shared without permission. Proprietary and Confidential.

Additional Project Details Wide Connected Load Range: ~75kW (min.) – ~300kw (Peak) expected Daily Average Loads: 1,800 – 3,000 kw-Hr/day Inverter-Based PV/Wind Grid Inverters provide system frequency & voltage reference Very fast response to load change Efficient energy conversion thru wide load range Bi-directional Inverter/Charger to manage battery bank SOC Higher degree of WTG penetration than traditional WD/diesel grid

©2009. Northern Power Systems. All Rights Reserved. Not to be used or shared without permission. Proprietary and Confidential. Challenges to Project Grid Impedance May Be Higher Than Typical Diesel Grid Final System Optimization May Require Turbine Control Adjustments Dispatch Coordination Between Inverters & WTG Critical to Performance Stability 120 Ton Installation Crane delivery and Concrete dispatch Unique advanced system configuration Island time, expect the unexpected Battery Life and Cost to Maintain Hurricanes

©2009. Northern Power Systems. All Rights Reserved. Not to be used or shared without permission. Proprietary and Confidential. Promote Creative Solutions to Get Us Off Fossil Fuels! Higher Degree of Penetration (diesel offset) Possible Common DC Bus Supports Separate Inverter Sources for Redundancy Split Power System- Balancing Different Feeds from Same Source Verified Inverter-Based System Inverter Will Control Frequency & Voltage W-D Control Integration Similar to Diesel Integration No Fossil Fuels!