Skip to content

Siam Yamato Steel Rayong plant

operating

Maptaphut, Asia Pacific, Thailand

ISO 14001ISO 50001
GEM wiki

Process Route

EAF

Timeline

Operating since 2010

Emissions

2025

0.02 Mt CO₂e

0.08 t CO₂e per tonne of steel

Typical EAF route: 0.5–0.7 t/t

Modelled estimate (Climate TRACE), not reported data. Methodology

Capacity (ttpa)

Crude Steel

500

EAF

500

Steel Units

EAF
unknown EAF (1)operating
500 ttpawiki

Inputs & Energy

Power solar panels

Steel Products

piling, channel, i-beam, angle, h-beam, beam

Ownership

Owner Siam Yamato Steel Co Ltd

Parent Yamato Kogyo Co Ltd [64.2%]; Mitsui & Co Ltd [20.0%]; Siam Cement PCL [10.0%]; Sumitomo Corp [5.8%]

State ownership Partial

Country Context

Thailand crude steel production (USGS). Plant line shows nominal capacity, not output.

Explore

Plant data sourced from the Global Iron & Steel Tracker (March 2026), Global Energy Monitor. Licensed under CC BY 4.0.

Production data: USGS Minerals Yearbook — Raw Steel: World Production by Country or Locality (2019 edition; 2022 and 2023 early release tables). U.S. Geological Survey, public domain. EAF/BOF splits: USGS Minerals Yearbook (2023 estimates).

Facility emissions estimates from Climate TRACE. Licensed under CC BY 4.0.