The New Gas Power Revolution That Could Make Renewable Energy Obsolete

If the Net Zero power plant performs as expected this is a real game changer for natural gas. Since the United States is sitting on more natural gas than any country in the world, and it’s getting cheaper to get it out of the ground, this is no small game to change.

An
actual game changing technology is being demonstrated as we sit in
our air-conditioned abodes reading this. And it is being demonstrated by North
Carolina–based Net Power at a new plant in La Porte, Texas.

*NET Power’s 50 MWth Demonstration Plant in La Porte, Texas. NET POWER*

The
process involves burning fossil fuel with oxygen instead of air to generate electricity without
emitting any carbon dioxide (CO2). Not using air also avoids generating NOx,
the main atmospheric and health contaminant emitted from gas plants.

Included in a group of
technologies known as carbon capture and sequestration (CCS), zero-emission fossil
fuel plants have been a dream never realized in practice, as it always seems to cost a lot, adding between 5¢
and 10¢ per kWh. This is probably because most attempts just add on another
step after the traditional electricity generation steps, almost as an
afterthought.

Some
fossil fuel plants have tried, and failed, the most famous one recently being
the $7.5 billion coal power plant in Kemper, Mississippi.

But
this new technology completely changes the steps and the approach from the
ground up. It is based on the Allam Cycle, a new, high-pressure, oxy-fuel,
supercritical CO₂ cycle that generates low-cost electricity
from fossil fuels while producing near-zero air emissions.

All
CO₂ that is generated by the cycle is produced
as a high-pressure, pipeline-ready by-product for use in enhanced oil recovery
and industrial processes, or that can be sequestered underground in tight
geologic formations where it will not get out to the atmosphere for millions of
years.

The Allam Cycle also means the power plant is a lot smaller and can be sited in more areas than older plants can.

*The Allam Cycle of Net Power’s new zero-emission natural gas plant. NET POWER*

This
50 MW Texas plant is demonstrating that the technology works, especially to
investors. So the project has some heavy hitters as partners – Exelon Generation will operate the plant, the infrastructure firm CB&I will
provide engineering and construction, 8
Rivers Capital, Net Power’s parent will provide continuing technology
development, and Toshiba will
develop the key components, particularly its new CO2-turbine.

Most
power plants rely on thermal power cycles for energy production. These systems
create heat by burning fossil fuel using the oxygen in air. In coal
plants, this takes place in a large boiler, where coal is burned and water is
boiled to create high pressure steam. This high-pressure steam then
expands through a steam turbine, creating power.

In combined cycle gas turbine
power plants, natural gas or coal syngas is burned in a combustor
with compressed air. The heated gases then expand and drive a gas
turbine. The turbine exhaust is extremely hot, so it is subsequently used
to boil water to create high pressure steam and drive a steam turbine, thereby
combining cycles. In both systems, aqueous steam is essential to the process as
a working fluid.

Not so in an Allum Cycle
plant like Net Power’s. At their Texas demonstration plant, the natural gas is
burned with a mixture of hot CO2 and oxygen, known as oxy-combustion. The
resulting working fluid is a mix of high-pressure CO2 and water, which is
subsequently expanded through a turbine and then cooled in a heat exchanger (a
recuperator).

This is key. The turbine is not turned with steam, but with CO2.