coal‐fired generation capacity has been delayed for years and this trend seems to continue. The Rampal power plant has been in development since 2010 and construction only recently began. The Matarbari coal plant project has seen a similar slow development to date. Beyond these known coal projects, we have also allowed for generic coal projects at $1,800/kW for an additional 1,200 MW that can be commissioned from 2023.

The addition of new gas and oil generation capacity has been more seamless due, in part to experience and to private sector participation. The Siddirganj Power Plant, a 335 MW CCGT, recently began operation and several new CCGT plans are set to start this year and next. Summit Energy developed two new 335 MW power plants near the Bibiyana gas field in the North and an additional 225 MW will come online on the island of Bhola this year. In addition to these known projects, the model allows for generic open cycle and efficient combined cycle gas turbines at a cost of $940/kW and $1,250/kW, respectively.

To meet growth in power demand, the government has opened up the generation sector in 2005 for private companies and, since then the sector added 2 GW of fuel oil generation. A recent tender called for an additional 10 ‐ 100 MW each ‐ fuel oil generators set to be located around the country. The decline in oil prices also eased the fiscal burden on BPDB as the single buyer of all power, including fuel oil based power. As noted above, private generators can now import fuel oil at essentially international prices. Given the delays in coal generation, the development of more fuel oil capacity remains likely. The model allows for up to 900 MW of additional HFO based generation capacity.

The data for existing generators uses reported fixed costs, variable operating and maintenance costs, heat rates, retirement dates, and international fuel prices. Plant level data comes from the Bangladesh Power Development Board’s System Planning division. For state‐owned generating units, the dataset provides fixed and variable costs. For private generators, the data available pertains to the fixed and variable costs as defined in the power purchase agreements. The two sets of costs differ as the latter includes economic costs and rate of returns for each generator. Given that economic data is unavailable for private generators, the reported contractual terms serve as a proxy.

New build capacity costs are based on industry assumptions for capital and operating and maintenance (O&M covering both fixed and variable) costs. Such capital costs are amortized over the life of the plant and appear as annualized capital costs. A weighted average cost of capital (WACC) was used to calculate annualized capital costs. The power sector in Bangladesh relies increasingly on new generation capacity by private companies. The cost of capital varies across the projects depending on the source of financing and underlying interests. The Rampal coal power plant project, for instance, is a joint venture between state‐owned power companies from India and Bangladesh. The project received a concessional finance from the Government of India and hence its amortized annual fixed costs take into account the (lower) interest rate reported on the loan.

Hourly solar resource data, an input into the model, comes from Solargis. Global Horizontal Irradiance (GHI) data aggregates direct and diffuse solar irradiation on an hourly basis for South Asia, including Bangladesh. This solar resources data is available with a 1km by 1 km resolution. A comparative analysis of GHI data for different parts of Bangladesh shows little variation of irradiation across the country. We, therefore, assumed a single point reference for the entire system, an assumption that is also supported by minimal prior work on site selection. Given Bangladesh’ high population density, high flood risk, and extensive reliance on agriculture, site selection for utility‐scale projects will indeed be a critical issue.

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