Klasyczne refers to conventional, which refers to operation in the subcritical regime.

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Home » Glossary » PQRS » Supercritical & Ultra-supercritical technology
Supercritical & Ultra-supercritical technology
Similar term(s): SC and USC power plants.
Definition:
Conventional coal-fired power plants, which make water boil to generate steam that activates a turbine, have efficiency of about 32%.
Supercritical (SC) and ultra-supercritical (USC) power plants operate at temperatures and pressures above the critical point of water, i.e. above the temperature and pressure at which the liquid and gas phases of water coexist in equilibrium, at which point there is no difference between water gas and liquid water. This results in higher efficiencies – above 45%.

http://www.greenfacts.org/glossary/pqrs/supercritical-ultra-...

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A supercritical steam generator is a type of boiler that operates at supercritical pressure, frequently used in the production of electric power.

In contrast to a subcritical boiler in which bubbles can form, a supercritical steam generator operates at pressures above the critical pressure — 3,200 psi or 22 MPa. Therefore, liquid water immediately becomes steam. Water passes below the critical point as it does work in a high pressure turbine and enters the generator's condenser, resulting in slightly less fuel use and therefore less greenhouse gas production.

Technically, the term "boiler" should not be used for a supercritical pressure steam generator as no "boiling" actually occurs in the device.
https://en.wikipedia.org/wiki/Supercritical_steam_generator
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Subcritical, Supercritical, Ultra-supercritical, and Circulating Fluidized Bed (CFB)
Virtually all coal plants in current operation employ pulverized coal combustion technology, which involves grinding coal into talcum-powder fineness and then burning it to heat water into high-pressure steam to drive an electrical generator. The difference between subcritical, supercritical, and ultra-supercritical versions of pulverized coal combustion technology has to do with the steam pressure within the boiler. In a subcritical plant, steam pressure is below 3200 pounds per square inch and temperature is below 1025 degrees Fahrenheit (550 degrees Celsius). Subcritical units have efficiencies of between 33% and 37%; i.e. between 33% and 37% of the energy in the coal is converted into electricity. In the late 1960s, supercritical combustion technology was commercialized, after advances in materials technology made it possible to build boilers that could operate at higher pressures. In supercritical units, the pressure of the boiler is about 3530 pounds per square inch and temperatures are 1050 degrees Fahrenheit (565 degrees Celsius). At this higher pressure and temperature, water can be maintained as a fluid despite being above the atmospheric boiling plant, allowing greater efficiency. Efficiency ratings for supercritical coal plants range from 37% to 40%. In ultra-supercritical units, pressures are at 4640 pounds per square inch and temperatures of 1112-1130 degrees Fahrenheit (600-610 degrees Celsius), and current research and development is targeting pressures of 5300-5600 pounds per square inch and temperatures of 1290-1330 degrees Fahrenheit (700-720 degrees Celsius), with the possibility of raising generating efficiency to the 44-46% rangeal.[1]

In fluidized bed plants, coal is burned with air in a circulating bed, typically made of crushed coal combined with limestone The advantage of this technology is that it is suited to a wide variety of coals and no-coal fuels such as biomass. An advantage of CFB technology is that it favors low NOx formation and capture of SO2. Efficiencies are comparable to subcritical and supercritical plants.[1]


http://www.sourcewatch.org/index.php/Coal_power_technologies