This paper provides detail of the inter-regional system of analysis of East Asia (IRSA-EA). IRSA-EA is a static and multi-country computable general equilibrium (CGE) model. IRSA-EA has a flexible production structure that allows substitutions among electricity and energy intermediate inputs. Hence, the model can simulate the impacts of changes in energy and electricity prices. Also, the model incorporates several recycling mechanisms to simulate the impacts of renewable electricity development and decarbonisation in the East Asia region. This paper provides a technical guide for the IRSA-EA model that will be useful to analyse the socio-economic and environmental impacts of policy instruments in the subsequent two papers.