# Presentation: 191820

## 	Distributed Generation  	Con Edison

**	****Distributed Generation  ****	****Con Edison**
**        **

- A.Kaffashan / M.Rollins
- April 23, 2004

## Con Edison Electric Distribution System

- Con Edison Electric Distribution System

- 			**Area:****	****	****	****604 sq mi****	****	****Population:****	****	****	****8,800,000**
**	****	****Electric Customers:****	**
**	****	****Total:****	**** ****	****	****	****3,200,000 **
**	****	****Network:****	****	****	****2,300,000**
**	****	****Radial:****	****	****	****835,000**
**	****	****Peak Load (2001):****	****	****12,207 MW**
**	****	****	****	**

##  Design Basis of Distribution System

**Second Contingency **
**High density load areas**
**Urban and financial districts**
**First Contingency **
**Low load density areas**
**Suburban area**
**Separation of feeders**

## Network Characteristics

**High Reliability**
**Totally Underground**
**Multiple Feeders **
**Multi-level Electronic Monitoring and Control Capabilities**
**Analytical Capabilities**
**Real-Time Remote Control**

**Notes:**
Second Contingency
Not Susceptible to Weather Conditions
Redundancy

## Electric Distribution System Networks

**	****Networks****	****                                          56**
**	****Feeders****	****                                           897**
**	****Network Transformers****	****            24,000**
**	****Manholes & Boxes****	****                  260,000****	**
**	****Primary Feeder Cable****	****       27,000 km**
**	****Secondary Cable****	****                80,000 km****	**

## Con Edison Electric Distribution System

**Network:****	****Many simultaneous paths for power to flow to****	****customers.**
** ****Each network is fed from one area substation.**
** ****Typically:****	********12 - 24 primary feeder**
**	****	****	********250 - 750 transformers**
**	****	****	********7,500 - 75,000 customers**
** ****Of 56 major networks****	********33 in Manhattan**
**	****	****	********10 in Brooklyn**
**	****	****	********7 in Queens****	**
**	****	****	********6 in Bronx**
** ****Except for Manhattan, other Areas have extensive**
**   ****amounts of isolated networks and radial distribution.**

## Networks Elements

- 	_**T**_ransformer: Transform the voltage from primary (13 or 27 kV) to 		          secondary (120 volts).
- 	_**N**_etwork Protector:  Isolate network from primary feeder fault.
- 	_**F**_uses:	On each network protector to backup for primary 	feeder fault &
-        	secondary fault.
- 	_**L**_imiters:  Weak links on each cable end to isolate 	secondary faults to a single
- 		    section of cable.

## Simplified Area Network Schematic

- Distributed
- Network
- Grid is 120/208

- Isolated
- Network

- Transformer

- Customer Load

- Network Protector
- and Fuse

## Typical Area and Spot Networks

## High Tension or High Rise Building

**High Rise**

**125/216V or277/480V **

**NWP**

**2500kVA each**

**2500, 3700, 5000kVA each**

**4 or 13KV**

**13, 27 or 33kV**

**CB (Typ.)**

**S/S Bus**

**Large Commercial or**
**Industrial Customer**

- Z

## Interconnection Process

- Preliminary Discussions
- Major Considerations of Combined Heat and Power
- Method of Electrical Connection
- Application and associated documentation
- Site-specific review by Con Edison
- Detailed Specifications
- Design and O&M Specs Developed by Con Edison
- Signed by both the customer and Con Edison
- Verification Testing
- Procedure developed by customer
- Witnessed by Con Edison forces
- Interconnection Charges
- Costs related to the DG billed to the customer

## Interconnection Process

- Major considerations of CHP installation:
- Con Edison:  How does the proposed generator affect the existing electric system?
- Available  Short Circuit Current
- Fault Current added by the CHP
- Building Load with respect to the size of the CHP System
- Will the CHP system be a “Qualified Facility? ”
- Is the system approved and type tested in accordance with the NYS SIR?
- Site:  Is there a continuous minimum electrical and mechanical load to allow the CHP system to continuously run efficiently?

## Fault Current added by the CHP

- Area Substation Fault Duty Limitations

## Effect of CHP System Sizing

- A short circuit study determines the available fault current
- Customer load must be evaluated to size generator(s)

## Interconnection Process

- Method of Electrical Connection (Operating modes)
- Supplemental (parallel): CHP system runs continuously, Con Ed provides difference
- Buy-back:  not allowed on distribution network system (SC11)
- Standby: CHP system runs continuously, providing all loads, Con Edison available if CHP system is down (SC14RA)
- Isolated: no interconnection with Con Ed system

## Interconnection Process

- Application and associated documentation

- Con Edison (Networks)
- I. Service Address
- II. Account Information
- III. Service Description
- IV. Contractor Info
- V. Generator Data
- VI. Description of System Operation
- VII. System Drawings

- NYS SIR (Radial Feeders)
- I. Project Contact
- II. Application Fee
- III. System Drawings
- IV. Equipment Description
- V. Verification Test Procedure
- (presently limited to 300 kVA)

## Interconnection Process

- Site-specific review by Con Edison

- Con Edison (Networks)
- I. Voltage Protection
- II. Frequency Protection
- III. Reverse Power Relay *
- IV. Directional O/C **
- V. Sync Check Relaying **
- DISCONNECT SWITCH

- NYS SIR (Radial Feeders)
- I. Voltage Protection
- II. Frequency Protection
- III. Site Specific Relaying **
- IV. Dedicated Transformer *
- V. Net Metering
- DISCONNECT SWITCH

## Interconnection Process

- Network interconnection protection requirements in: *Con Edison Handbook for Dispersed Generation*
- Anti-islanding protection (81U/O, 27/59)
- Reverse power protection (32R)
- Network protector interlocks
- Overcurrent protection (50/51)
- Synchronizing & sync check functions (25)
- Disconnect switch (89)

## Interconnection Process

- Detailed specifications
- Design specifications developed by Con Edison to indicate specific equipment required for interconnection of CHP system
- O&M specifications developed by Con Edison to indicate the methods to be followed when starting and working with the CHP system
- Final agreement between the customer and con Edison

## Interconnection Process

- Verification testing
- Procedure developed by customer to show Con Edison how the control and protection equipment performs as designed
- Procedure approved and witnessed by Con Edison

## Interconnection Process

- Interconnection charges
- Engineering review of information submitted during application
- Cost to perform work on Con Edison system to allow for the interconnection of CHP system