copper alloy conductors for overhead lines - nordic conference on electricity distribution system

New generation of copper conductors for overhead lines NORDAC, September 2014 European Copper Institute – [email protected]

| Copper OHL - NORDAC 2014 2

COPPER ALLIANCE

Copper Alliance International Copper Association

> 50 years leading

organization in copper

promotion

43 global members:

copper producers and

fabricators

Sustainable Energy as one

of core initiatives

> 500 local members and

partners

3 | Copper OHL - NORDAC 2014

Moderador

Notas de la presentación

Copper Alliance includes many legal entities around the world going by different names e.g. ECI in Europe, CDA in USA, DKI in Germany etc. and ICA is the parent organization The ICA is responsible for guiding policy and strategy and for funding international initiatives and promotional activities on behalf of our members. Headquartered in New York City, the organization has offices in four primary regions: Asia, Europe and Africa, Latin America and North America. In 2011, the ICA Network adopted a branding campaign referred to as Copper Alliance™. Use of the Copper Alliance™ brand enables the ICA Network to maintain a stronger web presence and better position copper centers within the ICA Network to support their respective geographic markets.

Sustainable Energy Promotion of mature technology

Renewables

Energy Efficiency

Home Electricity

Building Automation

Electrical Safety

Power Quality

Clean Energy Regulators Initiative


Technology Development and Transfer Market introduction of new technology

Sustainable fish farming

Anti microbial surface

Air conditioning / heat exchangers

Electrical vehicles: motors and batteries

Gas water heaters with improved heat exchangers

Power and data over Ethernet cables

Earthquake protection



NEW GENERATION OF COPPER CONDUCTORS FOR OVERHEAD LINES

Advanced copper alloys largely exceed Cu ETP used in the past


http://www.conductivity-app.org/alloy-sheet/33 http://www.lafarga.es/en/products-and-markets/overhead-lines-conductors/cables-mt-ht-et-tht

Cu ETP (past)

Cu Alloy (present)

Breaking load (MPa) 220 500

Conductivity (IACS) 100% 95%

Coefficient of thermal

expansion 10-6/K 17,7 16,8

> Twice strength

Preserved conductivity

Lower expansion

Moderador


Why copper in OHL, while the choice was abandonned several decennies ago? We are not talking about the same copper product as used in the past. Thanks to the recent intensive research in alloys (driven among others by the extreme requirements of high speed railway catenary systems), we have today high technological products with outstanding properties.

http://www.conductivity-app.org/alloy-sheet/33

http://www.lafarga.es/en/products-and-markets/overhead-lines-conductors/cables-mt-ht-et-tht

Additional features of advanced copper alloys - 1


Operating temperature 150ºC – 200ºC

• High annealing temperature, creep free up to 200ºC or higher

• Offers extra 60% up to 100% spare capacity beyond 80ºC

EDS > 25%, even 30% • Fatigue – resistant, strength can be largely

exploited • Well featured against galloping

Corrosion-proof • Copper performance against corrosion • Additionally supported by coatings

Additional features of advanced copper alloys - 2


Hydrophobic • Thanks to the high annealing

temperature of copper alloys, special coatings can be applied (which require high temperatures of deposition)

• Coating color is tailor made (anti-theft, mimetic with environment…)

Dielectric: no skin effect

Dielectric: reduced Corona losses & noise

COATINGS


COPPER OFFER TO SYSTEM OPERATORS

Copper offer to System Operators - 1


N-1 ENERGY EFFICIENCY

• 60% to 100% spare capacity when allowing conductor temperature increase

• Redistribution of power flows / Higher penetration of variable renewables

• Saves alternative investments in generation or T&D capacity

• 60% more conductivity than aluminium for equal section

• No skin effect (+ 10% conductivity)

• Article 15 of Energy Efficiency Directive

Moderador


Energy Efficiency: article 15 -> “Member States shall ensure, by 30 June 2015, that concrete measures and investments are identified for the introduction of cost-effective energy efficiency improvements in the network infrastructure”

Copper offer to System Operators - 2


DEMANDING WEATHER

CONDITIONS

Wind load Weight + ice load

Weight

Wind load

ACSR

COPPER

• Wind load: bigger conductor diameter + ice layer

• Wind load: smaller conductor diameter, reduced or no ice layer (hydrophobic coating)

Moderador


Despite its higher weight, copper can use up to 60% less section for equal conductivity than aluminium (even bigger differences when considering the poor conductivity of steel in ACSR). In windy and icy climates, the predominant strength component is the wind load, due to the increased section following ice accretion. Copper conductors offer a reduced section that, thanks to its hydrophobic coating, is much less sensitive to ice accretion, resulting in a lower net effort on the conductor.

Where copper alloys add value


WINDY / ICY

CORROSIVE

RECONDUCTORING

IMPLEMENTING ENERGY EFFICIENCY

Moderador


Windy areas >120 km/h Cold regions Corrosive atmospheres (marine, salty environments) Upgrade of existing lines, particularly valuable in distribution networks, where the simplicity of the copper conductor is an added value compared to other complex conductors featured for upgrades. Either existing copper conductors (where substitution by ACSR is not possible because of higher wind loads non-compatible with the existing towers) or ACSR conductors.


PILOT PROJECTS

Ongoing pilot projects with copper alloys


Codelco copper mines

Private line 20 km

• DSO Endesa, Pyrenees: 1,5 km -> Ice accretion

• DSO Endesa, Salt mine: 1,5 km -> corrosion

• DSO Estabanell: 20 km -> reconductoring an existing copper overhead line


Summary

Summary


• Advanced copper alloys offer a competitive conductor for a number of niche applications: • Severe climate conditions • Corrosion • Upgrade of existing lines

• Technical feasibility has been assessed by DNV KEMA

• Economic benefits proven: • New lines: higher energy efficiency, lower life cycle cost, short payback time • Existing lines: in range with HTLS, but lower losses and simpler to install

Thank you


For more information please contact

European Copper Institute - Fernando Nuño [email protected]

La Farga - Gustau Castellana [email protected]

mailto:[email protected]

mailto:[email protected]


DNV KEMA analysis Part 1 : new line

Conductors compared

ACSR – Hawk LA 280


ACSR Eagle LA 350

Copper conductor

CAC 185

Additional considered conductors (under the same current conditions)

700 A @ 80ºC Higher investment

Lower losses

700 A @ 80ºC / 1115 A @ 150ºC Higher investment

Lower losses

630 A @ 80ºC

Conductor specification


ACSR Hawk ACSR Eagle CAC 185

Cross section (mm2) 280 350 185

Current capacity at 80°C (A) 630 700 700

Current capacity at 150°C (A) - - 1115

Weight (kg/km) 982.3 1301.8 1652

Electrical resistance (Ohm/km) 0.1195 0.103 0.09

Tensile strength (kN) 85 123.6 93

Elasticity (kN/mm2) 77 81 50

Thermal expansion (1/°C) 0.0000189 0.0000178 0.000017

Max operational temp (°C) 80°C 80°C 150°C

Simulated route

70 km – 220 kV Double circuit

Simulated but realistic route


• PLS-CADD • Based on standard EN 50341-1:2001 • Overhead line route is optimized for each

conductor type, based on the specified conductor properties.

• Tension vs suspension towers: 1:5

DNV KEMA study

Scenarii


Load profile Cost of losses Time horizon

• 5 c€/kWh • 7 c€/kWh

0%

50%

100%

0% 50% 100%

Load Profile 1

0%

50%

100%

0% 50% 100%

Load Profile 2

• 15 years • 20 years

DNV KEMA study

Assumptions


Projections Cost of conductors

• ACSR Hawk: 4 €/m • ACSR Eagle: 5 €/m • Copper 185 mm2: 15,5 €/m

• Inflation: +2% / year • Electricity:

• + 2,00% from year 1 to 10 • + 0,77% from year 11 to year 20

DNV KEMA study

Conditions


80°C bundle current (A) per wire (A) Perc. of HAWK Case 1 HAWK 4 1880 470 100% Case1b EAGLE 4 1880 470 100% Case 2b Cu T1b 4x185mm2 4 1880 470 100%

Load cases as per EN 50341-1:2001

• LC 1a – Extreme wind at design temperature • LC 1b – Wind at minimum temperature • LC 2c – Unbalanced ice loads, different ice loads per

span LC 3 – Combined wind and ice loads

Same current in all

cases

Copper vs ACSR Payback time: 5 - 7 years Life Cycle Cost: lower by 10% - 20%


ACSR Hawk LA 280

ACSR Eagle LA 350 Copper CAC 185

Cost of losses 183,5 174,9 138,0 Conductor cost 6,8 8,4 21,7 Stringing conductor 6,8 6,8 6,8 Towers & Foundations 32,3 33,9 29,2 Maintenance NPV 20 years 5,7 5,7 5,7

0

50

100

150

200

250 M

€ Breakdown of Life Cycle Costs for new lines (M€)

Cost of losses

Conductor cost

Stringing conductor

Towers & Foundations

Maintenance NPV 20 years


DNV KEMA analysis Part 2 : refurbishing an existing line

Copper vs ACSR Same capacity upgrade as ACSS Lower losses, lower life cycle costs


ACSR Hawk

@80ºC

ACSS Hawk

@150ºC

Copper CAC

4x165 mm2

@150ºC

Copper CAC

3x240 mm2

@150ºC Cost of losses 183,4 518,2 458,2 419,8 Conductor cost 6,8 8,4 19,4 21,2 Stringing conductor 6,8 6,8 6,8 6,8 Towers & Foundations 32,4 0,0 0,0 0,0 Maintenance NPV 20 years 5,7 5,7 5,7 5,7

0

100

200

300

400

500

600 M

€

Breakdown of Life Cycle Costs for upgrade of existing lines (M€)

Cost of losses

Conductor cost

Stringing conductor

Towers & Foundations

Maintenance NPV 20 years