Project Summary
Low NOx, Low
Particulate Reciprocating Engine with Better Than Diesel Efficiency
Dr. Robert W.
Dibble, Panamint Technology
99-29
The purpose of the
proposed project is the development of a generator set powered by a
reciprocating engine running in the
Homogeneous Charge Compression Ignition (HCCI) mode. Laboratory research
has demonstrated the capability of HCCI engines operating on natural gas to produce
NOX emissions in the 10 ppm range in combination with virtually no particulate
matter and thermal efficiencies equal to, or greater than, Diesel engines
(-45%); in short, a Diesel replacement. This technology, in conjunction with
proprietary control strategies, will be utilized to open new markets to
stationary natural gas engines and eventually to vastly improve mobile
transport emissions.
While the HCCI concept has been under investigation for over
20 years it has yet to find a significant market due to difficulty in engine
control and limited range of operating conditions. The advent of new sensors
and microprocessor driven control systems now allow this technology to be
utilized in applications which do not require a wide operating range; a first
application being stationary power generation. As we learn from stationary
applications, mobile systems will
follow.
The primary issue facing the application of HCCI technology
to power generation markets is controlling the start of combustion (SOC) in
each cylinder on each cycle. Early SOC increases mechanical stress and engine
noise and prevents maximum thermal efficiency, and thus must be closely
controlled. Late SOC must be
prevented as it leads to incomplete combustion. As spark plugs and in-cylinder
fuel injection are not utilized, control of SOC is the primary challenge.
A novel combination
of sensors will allow direct measurement of the start of combustion and overall
combustion duration. These parameters will than be manipulated on a cycle
to cycle basis by controlling the
full range of engine and generator operating conditions.
Phase 1 of this project is addressing the distributed power
generation market. Current generator set providers are limited, by legislation,
from selling their products into emissions sensitive areas. The development of
the proposed HCCI engine driven generator will allow unlimited access to these
products as well as displacement of higher polluting diesel generators and
engines that are less than 30% efficient e.g. SI engines and typical micro-turbines.
The successful completion of this project will provide a
compete HCCI engine driven generator
which will be marketed by current co-generation and distributed power providers. The market penetration of these
engines will reduce emissions and provide
cost savings to the rate payer due to reduced fuel consumption and lower
first cost.
The development of an economically viable, low emissions,
high thermal efficiency generator set
for the distributed power market would constitute success in this project.
The product that will be developed will be of value
both to producers of engine driven
generators and to end users of distributed power. A number of generator set
manufacturers have expressed interest as this project will significantly expand
the market applicability of their products.