If steam can be compressed to higher pressure from lower pressure, that will have many many applications than just power generation. Steam is used in many kind of industries and a huge amount is wasted at present as steam compressors will consume more energy and they are costly and therefore making new steam by using conventional fuel is cheaper in comparison to compressing low pressure steam to higher pressure. But, if the power consumption can be reduced by any means, much less fuel will be burnt and that means lower GHG emission.
As for example, at present it will take around 800 kW (multiple stage compressor with intercooler) to compress steam from 2.536 kPa (saturated steam pressure at 20C) to 1 bar @ 1 kg/sec. While the amount of heat embedded in 1 kg/sec steam flow is around 2.6 MW. Now, if we consider that the electricity comes from a thermal power plant with around 33% efficiency, that means it will take 2.4 MW of heat to produce 800 kW of electricity and at the end we will just have left with 200 kW of heat, a mere return against huge investment in steam compressor. But, if the steam will remain in saturated state during the whole process, that amount can be reduced to just 200 kW and you yourself can calculate the increase in the amount of additional heat which can make the investment in steam compressors more attractive and can save huge amount of fuel.
