Summary Overview: Maryland Straw Man Interconnection Rule Prepared by Brad Johnson* January 11, 2007 ACN Energy Ventures *National Renewable Energy Laboratory Subcontractor MARYLAND INTERCONNECTION WORKSHOP

2 Technical Requirements (IEEE no exceptions & no additions) Administrative Procedures (Based on Pennsylvania with Oregon updates -- 3 levels of expedited review) Testing (Certification requirements, standard agreement provisions & IEEE ) Maryland Straw Man Rule: Key Elements

3 Straw Man Based on FERC and Pennsylvania Procedures With Oregon Updates FERC Small Generation Rules (May ’05) –Culmination of multi-year national stakeholder process –In spite of limited jurisdiction, rule represents broad consensus and is good blueprint for states PA Interconnection Rule (September ’06) –Paved new ground for expedited review procedures (area networks and non-exporting equipment) –Integrated testing & certification requirements Oregon (‘06-’07 Working Group Activity) –Expanded certification concept to include field certified equipment (qualifies for expedited review) –Simplified expedited review procedures

4 Straw Man Overview Procedures have four categories of review –Level 1 <10kW, inverter based/lab certified –Level 2 <2 MW, lab or field certified –Level 3 <10MW, DG does not export power, provision for area networks –Level 4 <10MW, does not qualify for or has previously failed expedited review Technical requirements based on IEEE 1547 – no exceptions and no additions Testing requirements are integral part of procedures and standard agreements Note: standard forms & agreements (based on MADRI/FERC ) will be developed separately from rule Expedited

5 Interconnection equipment certification is required for Level 1 or Level 2 expedited reviews Two types of certification:  Lab Certification – meets the requirements that NEMA meeting developed & FERC adopted, i.e. tested to IEEE by a NRTL & appropriately labeled  Field Certification – identical system has been approved by a utility in the state under a Level 4 study review within the prior 36 months (applies to Level 2 only). Certification Concept Based on Oregon Procedures

6 Straw Man Procedure Summary Level 1 Review (What qualifies) <10kW Inverter-based Lab certified interconnection equipment Does not connect to an area network

7 Straw Man Procedure Summary Level 1 Review (Technical Screens)

8 Straw Man Procedure Summary Level 1 Review (Timeline)

9 Straw Man Procedure Summary Level 2 Review (What qualifies?) <2 MW Projects that fail Level 1 review Lab certified interconnection equipment; or Field certified interconnection equipment Interconnection is to a radial distribution circuit or spot network serving one customer

10 Straw Man Procedure Summary Level 2 Review (Technical Screens)

11 Straw Man Procedure Summary Level 2 Review (Timeline)

12 <50kW Lab certified inverter Reverse power relays < 5% of max load on circuit or 50 kW No new facilities < 10 MW All generation on circuit < 10 MW Reverse power relays Dedicated transformer No new facilities Straw Man Procedure Summary Level 3 Review (What qualifies?) Area NetworkRadial Feeder

13 Straw Man Procedure Summary Level 3 Review (Technical Screens) <50 kW to Area Network  EDC may perform optional impact assessment at its own expense Connects to radial feeder  Same as Level 2

14 Straw Man Procedure Summary Level 3 Review (Timelines) <50 kW to Area Network  EDC has 25 days to perform optional impact study Connects to radial feeder  Same as Level 2

15 Straw Man Procedure Summary Level 4 Review (What qualifies?) Projects less than 10 MW Projects that do not qualify for expedited Level 1, Level 2 or Level 3 review Projects not approved under Level 1, Level 2 or Level 3 reviews

16 Straw Man Procedure Summary Level 4 Review (Elements of review process) Scoping Meeting to review interconnection request and existing studies Feasibility Study to review short circuit capability limits; identify thermal or voltage limits; grounding requirements; non-binding estimate of facilities cost System Impact Study to evaluate safety and reliability impacts including affected systems Facilities Study to estimate cost of equipment, engineering, procurement and construction work

17 Straw Man Procedures Summary Level 4 Review (Timeline Elements) Interconnection Request – EDC sends notice on status of completeness 10 days after receiving request, if deficient, customer has 10 days to complete Scoping Meeting held within 10 days of receiving notification of completed interconnection request Feasibility Study agreement provided within 5 days of determination that it is necessary System Impact Study agreement provided within 5 days of determination that it is necessary Facilities Study agreement provided within 5 days of determination that it is necessary

COMPARISON OF KEY DIFFERENCES BETWEEN STRAW MAN & FERC INTERCONNECTION REQUIREMENTS

19 Comparison of Straw Man and FERC Interconnection Technical Requirements 1.Isolation Device – Required. Device must be accessible, lockable, visible break type (primary lines) or device status must be clearly indicated (secondary lines); alternatives for customer to use lockbox to provide access 2.Generation may not cause protective equipment to exceed 85% of short circuit rating 1.Isolation device not specifically required 2.Generation may not cause protective equipment to exceed 87.5% of short circuit rating MADRI < 10 MWFERC < 20 MW Requires compliance with IEEE 1547References IEEE 1547

20 Comparison of Straw Man and FERC Review Procedures Level 1 (<10kW) – same as FERC Level 2 (<2 MW) - requires lab certified or field certified interconnection equipment Level 3 – expedited review for non-exporting systems on area networks (<50kW) and radial distribution circuits (<10 MW) In lieu of impact assessments, Level 1& 2 & 3 must satisfy impact technical screens Level 4 – study process for all other systems < 10 MW (virtually identical to FERC/PJM) Streamlined application for <10kW requires lab certified inverter based equipment Super-expedited for lab certified interconnection equipment < 2 MW. No provision for field certification No impact assessments for 1 & 2 above but must satisfy impact technical screens Study process for all other systems < 20 MW (virtually identical to PJM) No provisions comparable to Straw Man Level 3 MADRI (<10 MW)FERC (<20 MW)

21

22