**6. Utilities and power plant**

It is the components of the energy supply chain which generally provide energy in usable form to the end-users and also provide energy to the other components of the energy supply chain. Electricity is the most used secondary form of energy and power plants are the part of utilities that covert primary form of energy supplied by HCSC to electricity. Also, it is the component where high energy inefficiencies could have resulted. In 2017, the total power generation capacity of Saudi Arabia was 84 GW (100%), mainly from thermal sources (oil and gas). By 2030, it is projected to be 153–118 GW (65.5%) from fossil fuels, 58.7 GW (32.5%) from wind and solar, and 2.8 GW (2%) from nuclear [12]. This includes dedicated central power plants as well as industrial cogeneration. Other components of the energy supply chain need energy either as power or as heat, the conversion of primary energy to heat and power results in many configurations with differs a lot in terms of its efficiency.

### **6.1 Simple cycle power plant**

The vast majority of fossil fuel power generation in the world is based on a simple Rankine cycle with steam as the working fluid. Water is heated to generate high-pressure steam, driving a steam turbine to either electric energy through a generator. The steam turbine cycle is highly versatile, adaptable to any fuel that provides enough energy by combustion to vaporize water. The main drawback is that the power generation efficiency is limited to 30 to 40%, versus overall energy efficiencies of 55–80% for modern alternative cycles.
