Coal to Gas Capability Benefits & Impacts

Transcription

1 Coal to Gas Capability Benefits & Impacts Presented to: Southeastern Construction Owners & Associates Roundtable Edward C. Healy, P.E. October 13, 2016

2 Presentation Outline Southern Company Overview Southern Company Interest in Natural Gas Economic fuel for power generation Ability to leverage for MATS compliance MATS Overview Coal to Gas Capability Range of project costs Unit specific studies Typical coal to gas scope Schedule Emissions Brief Project Review Questions

3 Southern Company Overview

4 Southern Company Major Subsidiaries

5

6 Coal to Gas Spread

7 Nominal$/MMBtu Natural Gas Forward Price Curve Henry Hub Natural Gas Price Comparisons - Nominal$ AEO 2016 Ref AEO 2016 Ref w/o CPP AEO 2016 High economic growth AEO 2016 Low economic growth AEO 2016 High oil price AEO 2016 Low oil price AEO 2016 High oil and gas resource and technology AEO 2016 Low oil and gas resource and technology MISO - July 2016 NYMEX - September 20,

8 Southern Company Interest in Natural Gas Southern Company tripled its percentage of natural gas as a source of generation in the past decade Third-largest consumer of natural gas in the U.S. Natural gas is an effective environmental compliance tool Acquisition of Southern Company Gas (formerly AGL Resources) Better positions company to develop necessary natural gas infrastructure to meet customers growing energy needs Announced acquisition of 50 percent equity interest in Kinder Morgan s Southern Natural Gas pipeline system (pending)

9 Diverse Energy Mix

10 Mercury and Air Toxics Standards Emission rate (lb/mmbtu) standards for specified pollutants Mercury Non-mercury metals (measured as PM) Acid gases (measured as HCL or SO 2 surrogate standard) Does not apply to natural gas units Defined as: A unit that meets the CAA 112(a)(8) definition of an EGU but that combusts natural gas exclusively or in combination with another fossil fuel If the EGU combusts natural gas in combination with another fossil fuel, the natural gas must constitute at least 90% of the average annual heat input during any 3 consecutive years or 85% of the average annual heat input in 1 year.

11 Preliminary Cost Based on Literature $50 - $75 kw

12 Leveraging Natural Gas Study Units Boiler Class Plant Unit Nameplate Capacity (MW) Boiler Manuf Boiler Type Natural Gas Fuel Switch Study Unit CE Tangential fired A CE Tangential fired CE Tangential fired B CE Tangential fired CE Tangential fired <-- Nat Gas Study Unit CE Tangential fired Surrogate for Class 1 C CE Tangential fired CE Tangential fired D CE Tangential fired CE Tangential fired B & W Wall fired <-- Nat Gas Study Unit E B & W Wall fired Surrogate for Class B & W Wall fired B & W Wall fired F B & W Opp Wall Fired <-- Nat Gas Study Unit G B & W Wall fired Surrogate for Class B & W Wall fired H B & W Wall fired B & W Wall fired I Riley Front Wall Fired <-- Nat Gas Study Unit J Riley Wall fired Surrogate for Class 4 K B & W Wall fired B & W Wall fired No Study Unit L FW Wall fired M CE Tangential fired N CE Tangential fired No Study Unit CE Tangential fired

13 Site Specific Vendor Engineering Studies $40 - $50 B&W 272 MW B&W 250 MW kw Riley 250 MW Alstom 165 MW Alstom 350 MW

14 Gas Capability Cost (excluding Lateral) Group 4 (250 MW) Group 1 (183 MW) Class 2 (272 MW)

15 Coal to Gas Boiler Conversion Study Contracted with boiler OEM to conduct feasibility studies to evaluate boiler performance for converting from coal to natural gas firing. Approach was to determine boiler predicted performance while firing natural gas without pressure part modifications and identify components that may need to be modified. Components investigated include pressure parts, attemperators, burners, flame scanners, igniters, economizers and fans. In general, the converted boiler results in a lower flue gas flow, a higher FEGT and higher attemperation spray flows due to a shift from more radiant heat transfer for PC firing to more convective heat transfer for natural gas firing.

16 Coal to Gas Boiler Conversion Study Based on the results of modeling, estimated reduction in boiler efficiency ranged 3% to 6% In study boilers, all were able to maintain maximum continuous rating (MCR) main steam flow at superheater outlet conditions and reheat steam flow at reheater outlet Caution that predictions show tresses exceeding ASME s allowable limits in some pressure part tubes and headers.

17 Typical Dual Fuel Burner

18 Natural Gas Capability Wall Fired Burners

19 Natural Gas Capability Wall Fired Burners

20 Natural Gas Capability Wall Fired Burners

21 Natural Gas Capability Tangential Fired Burners

22 Natural Gas Fuel Skid at Burner Elevation Courtesy: WPCA Gas to Coal Conversion Seminar Alstom Power

23 Thermal Stresses in Convective Pass

24 Generic Natural Gas Capability Schedule Engineering Engineering Design Permitting Preparation Regulatory Review Transmission Build Gas Lateral Equipment Fabrication Construction Outage

25 Natural Gas Emissions VOC emission must be checked and could be an issue. Boiler CO emission on natural gas assumed to be lower than that of coal. Controls: assumed prudent combustion practice. Boiler NOx on natural gas is assumed to be ½ that of NOx on coal. Controls: SNCR or SCR SCR cost for asset valuation taken from mid-1980 boiler retrofits in California.

26 Uncontrolled Emission Rates Coal Natural Gas Units MCR Mid. Control MCR Mid. Control LOAD % NOx lb/10 6 Btu CO lb/10 6 Btu VOC lb/10 6 Btu

27 SCR / CO Arrangements

28 Gaston Units MATS Compliance Project

29 Gaston Units 1-4 Wall Fired Burners

30 Gaston Units 1-4 Simplified Flow Diagram

31 Key Project Milestones Milestones Activities Finish Date Construction Gas Lateral In Service Apr '15 COD - Aux Boiler Aug '15 COD Unit 4 Jun '15 COD Unit 1 Nov '15 COD Unit 2 Dec '15 COD Unit 3 Jan '16

32 Auxiliary Boiler

33 Natural Gas Conditioning Station

34 Greene County Gas Capabilities New Gas Infrastructure Burner Disassembly

35 Thank You for Your Attention Edward C. Healy, P.E. Southern Company Services 42 Inverness Center Parkway Birmingham, AL