Designing Supercritical CO2 Power Plants

The supercritical CO2 power cycle is one of the most promising power technologies. It is not by chance though, because carbon dioxide (CO2) has a unique combination of attributes, such as a low critical temperature, an environmentally natural origin, a high standard of safety and a low cost. Carbon dioxide is also thoroughly studied, therefore there is sufficient information surrounding it. But on the other hand, the supercritical CO2 cycle has a high energy conversion factor, such as high thermal efficiency.
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Co-generation Power Plants

The Kendall Cogeneration Station in Cambridge, MA
The Kendall Cogeneration Station in Cambridge, MA

Co-generation power plants are very popular in Europe compared to the U.S. market. It will be interesting to see if this type of application will take off in North America, but I’d like to share a little background information on co-generation first.
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New Waste Heat Recovery Features in AxCYCLE Available Now

AxCYCLE IC engine
AxCYCLE IC engine

Have you checked out AxCYCLE recently?

SoftInWay officially announced the latest features with the release of version 2.3.

With this update, the system’s new tools are available to all users, but waste heat recovery application engineers, particularly in the automotive industry, should take notice. Continue reading “New Waste Heat Recovery Features in AxCYCLE Available Now”

Should You Be Implementing the Organic Rankine Cycle?

To have a successful application of an ORC system, the availability of an adequate heat source is crucial. In principal every heat-generating process, such as burning fossil fuel, can be taken as a heat source for ORC.

However, the aim is to improve energy efficiency and sustainability of new or existing applications with the focus on waste heat and renewable energy sources.

Three sectors have been identified as potential sources for the application of ORC power generation: Continue reading “Should You Be Implementing the Organic Rankine Cycle?”

Cavitation Problems

Cavitation is not welcome in pumps. One of the most problematic effects of cavitation is the reduction in performance, but this is not the only problem! Cavitation can also cause damage to blades and create noise while the pump is working.

Perhaps, the most universal problem caused by cavitation is the material damage that bubbles can cause when they collapse in the vicinity of a solid surface. The problem is complex because it involves the details of a complicated unsteady flow combined with the reaction of the particular blade material. Continue reading “Cavitation Problems”

Carryover Losses – Steam and Gas Turbines

losses
Losses

A number of loss prediction methods exist in turbomachines. Concerning axial turbines, there are at least seven methods just for cascade losses! But there are also loss models developed to predict individual loss components such as secondary, seal and tip clearance losses and more. Continue reading “Carryover Losses – Steam and Gas Turbines”

Working Fluid in Organic Rankine Cycles

orcfluid
ORC Fluid

The choice of the working fluid for any given application is a key issue and should be done based on specific applications to achieve maximal efficiency. For working fluids in ORC, a green energy alternative, there are some requirements to keep in mind:

•Thermodynamic performance
Low pump consumption and high critical point

•Positive or isentropic saturation vapor curve
Avoid wetness in flow path, i.e. avoid damages of flow path elements

•High vapor density
Decrease sizes of equipment (expander and condenser)

•Acceptable pressures
High pressures usually lead to higher investment cost and increasing complexity

•High stability temperature
Prevent from chemical deterioration and decomposition at high temperatures

•Low environmental impact and safety level
•Good availability and low cost Continue reading “Working Fluid in Organic Rankine Cycles”

Retrofitting – When Steam Turbines Age

Steam-Turbine
Steam-Turbine

Statistics show that as a power plant reaches its rated lifetime, the number of its forced outages begins to grow substantially, and its reliability and availability fall.

Simultaneously, in the operation process the turbine’s efficiency lowers more and more, even though it is partially restored at overhauls.

It is possible to find steam turbines that have successfully operated for 40 – 50 years or more. Lately, power equipment lifetime extension has substantially gained in its scope and acquired much more serious significance. Continue reading “Retrofitting – When Steam Turbines Age”