This game would involve managing an energy company and would start around 1950. Companies would have to produce and refine fuels (coal, petroleum, natural gas, and uranium) and transport them for use (ships, railways, and pipelines). Once processed, the fuel can be sold directly to consumers or to utility companies that provide heat and/or power. There are natural gas companies for heat and other purposes, and also electric power companies that produce their power through various means. The fuel industry is subject to a lot of volatility that can make and break companies, while the utility industry is subject to regulated rates of return
(particularly on capital investments) that can provide a stable return on investment, although energy crises can lead to fuel price instability that can lose the company a lot of money. Players might also be able to play as investment banks and infrastructure companies (building transportation and power infrastructure, researching improvements, etc.).
Starting in the 1950s is key to this, as the energy sector was a lot more diverse. Petroleum was actually extensively used for power generation because it was more affordable than coal in some circumstances, and it was often considered more environmentally friendly at the time. Sulfur and acid rain was a major concern at the time, and while sulfur can be refined from petroleum flue gas desulfurization
wasn't a major technology at the time for coal (but maybe someone could research it earlier for coal). The 1950s was also the start of pollution and environmental regulations and the birth of the nuclear power industry, which was economically competitive during the 1960s.
Different fuel sources will have to play against each other to expand their market share in the rapidly growing energy markets of the post-World War II world. They can use pollution and environmental regulations against each other, not just between different fuel and energy sources but also between fuel companies and electric companies. Remember, electric companies get a regulated rate of return on prudent investments (especially capital investments), so they would support legal requirements to build and/or retrofit facilities with the latest technology, at least if they don't have connections with fuel provision. It could be a competitive advantage to avoid creating a fully integrated company, or it might be advantageous to do so in a way that plays the strengths and weaknesses of various fuel sources against each other. For example, a company involved in petroleum/natural gas (peaker plants are best used to fill power requirements in excess of minimum power supply requirements) could become involved in nuclear power (more expensive power plant cost, cheap fuel cost, best used to fulfill minimum power supply requirements). Even power plant suppliers could try to steer things different ways, such as lobbying for the government to purchase power plants for the federal utilities or install generating equipment at government owned isotope production reactors.
To prevent metagaming external shocks such as energy crises and issues with different fuel sources will be kept randomized. It isn't guaranteed that there will be a petroleum crisis in 1973 and 1979, but it also isn't guaranteed that a coal ash slurry pond, nuclear power plant, or hydroelectric station won't suffer a crisis that puts that energy source under scrutiny.