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.
Continue reading “Designing Supercritical CO2 Power Plants”

Which gas turbine is the best for my combined cycle power plant conversion?

combinedcyclesThe goal of this test case is to find the gas turbine necessary to produce 58 MW of total net power for the conversion of a steam turbine to a combined gas-steam cycle while providing the highest level of cycle thermal efficiency.

The exhaust gases from the gas turbine are used to heat up steam through three HRSGs (Heat Recovery Steam Generators) in series. The steam is then used in the studied steam turbine which is comprised of two “cylinders” in series.
Continue reading “Which gas turbine is the best for my combined cycle power plant conversion?”

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.
Continue reading “Co-generation Power Plants”

Shortening Start-Up Time and Life Prediction of Critical Components

steamturbine
Steam Turbine

This month we’re hosting the third segment to our Steam Turbine Webinar Series.

Shortening Start-Up Time and Life Prediction of Critical Components

Shortening  turbine start-up is a main concern for power machinery operators and manufacturers – is it a concern of yours? Continue reading “Shortening Start-Up Time and Life Prediction of Critical Components”

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?”

Components of an ORC Cycle

Schematic of an ORC system (R245fa is used here)
Schematic of an ORC system (R245fa is used here)

Organic Rankine Cycle (ORC) is a technology that can convert thermal energy at relatively low temperatures (80 to 350°C or 175 to 660°F) to actual work that can be further converted into electricity.

It is basically a thermodynamic cycle according to the Rankine principle but specifically uses organic fluids in order to have a boiling point at relatively low temperatures.

 

The heat is used to make the liquid boil and generate high pressure gases that will then drive equipment able to transmit torque to the shaft and create electrical power.
There are two main types of machines that are able to do this
• Turbine-based system
• Reciprocating piston-based system Continue reading “Components of an ORC Cycle”

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”

At a Glance – Turbochargers

turbocharger
Turbocharger

With the ongoing movement toward global environmental protection, regulations related to the exhaust emissions and fuel consumption of automobiles are being strengthened. To cope with these requirements, turbochargers are an effective tool to improve fuel consumption and reduce carbon dioxide emissions, by reducing the engine weight and friction loss.

Since a turbocharger supplies compressed air to an engine, it can reduce the engine displacement relative to an atmospheric engine for the same power. Variable geometry turbochargers, which can control the boost pressure according to the engine operating conditions, are becoming increasingly popular, creating a demand for a centrifugal compressor with a wide and stable operational range. Continue reading “At a Glance – Turbochargers”

Facts About Waste Heat Recovery for IC Engines

icengines
ICengines

Last month we hosted a webinar on waste heat recovery for internal combustion engines and beyond. You can view the webinar here.

This is becoming an increasingly popular topic in our industry and we’re seeing more information being posted from other industry professionals, so we thought this would be a great time to explain some basics about this energy efficient technology.

The situation:
A large part of the energy produced in an IC engine is lost to the surroundings but the waste heat from the engine exhaust and coolant is still an attractive energy source that reaches around 60% of the total energy converted from fuel. Continue reading “Facts About Waste Heat Recovery for IC Engines”

What’s An Ideal Heat Engine Cycle?

The Carnot cycle is the most efficient cycle possible for converting a given amount of thermal energy into work or, conversely, for using a given amount of work for refrigeration purposes.

Every thermodynamic system exists in a particular state. A thermodynamic cycle occurs when a system is taken through a series of different states, and finally returned to its initial state. In the process of going through this cycle, the system may perform work on its surroundings, thereby acting as a heat engine. Continue reading “What’s An Ideal Heat Engine Cycle?”