All internal combustion engines (ICEs) greater
than 50 brake horsepower (bhp) and gas turbines greater than 2,975,000
British thermal units (Btu) per hour are required to obtain a permit to
construct from the AQMD prior to installation of the engines at a site.
Most of the existing emergency backup generators
use diesel as fuel. Emissions of Nitrogen Oxides (NOx) from diesel-fired
emergency engines are 200 to 600 times greater, per unit of electricity
produced, than new or controlled existing central power plants fired on
natural gas. Diesel-fired engines also produce significantly greater
amounts of fine particulates and toxics emissions compared to natural gas
fired equipment. NOx is a primary component of smog. Engines operated on
fuels other than diesel, such as natural gas, ethanol, propane or with dual
fuels (diesel only for initial start-up and then primarily natural gas) are
much cleaner and produce significantly less air pollution for the same
amount of energy produced.
A standby ICE or turbine for non-utility power
generation that does not operate more than 200 hours a year and is only
operated in the event of an emergency power failure or for routine testing
and maintenance is considered an emergency backup generator for power
ICEs for emergency power generation that are fired
on natural gas only, and are permitted by the AQMD may be operated during Stage II or Stage III
electrical emergencies declared by the Independent System Operator (ISO) and
during actual or imminent blackouts. The hours the engines are operated
during these periods in any one year are accumulated toward the total 200
Operating the equipment in exceedance of the
permit condition limit of 200 hours is a violation and may result in a
notice of violation and a fine. To avoid the possibility of a violation,
the operator should petition the AQMD's Hearing Board for a variance to
operate in excess of the allowed 200 hours before it is anticipated that the
hours may be exceeded.
There is no guarantee that the Hearing Board will
grant or deny a variance. Each variance is evaluated on a case-by-case
basis, to evaluate emissions impacts, mitigations and other factors. While
it is not necessary, it may be prudent to hire an attorney or a consultant
to prepare and present the case and make the necessary findings before the
Hearing Board. You may contact the Hearing Board office at (909) 396-2500
for further information and for the variance application package.
Additional information can also be obtained from AQMD's website at
The permits that have been issued to the rental
yards are "Various Location Permits" and allow the operation of the engines
at different locations as long the specific permit conditions listed on the
permits are met. You do not have to obtain a separate permit to operate
this equipment at your facility; however you may be responsible for
reporting emissions from rental equipment to the AQMD.
b. Purchase or lease an engine that has
been certified by the AQMD.
The AQMD has certified certain models/families of
equipment as meeting all applicable air quality requirements and have issued
permits to the dealer/distributor of these engines. If you have purchased
or plan to purchase equipment from a manufacturer participating in the
program, be sure to pick up your application package from the
dealer/distributor. A list of dealers/distributors that are participating
in this program are available on AQMD's website at
http://www.aqmd.gov/prdas/spreadsheets/ICECertList.xls. You will have
to submit an application for a Permit to Construct/Operate this certified
engine and pay the reduced permit processing fee. These applications are
issued in an expedited manner.
c. Purchase or lease an engine that will meet
AQMD's BACT requirements.
If you plan to purchase a new or used engine from
a manufacturer/dealer or from a third-party, you will have to submit a
permit application and appropriate fees to obtain a Permit to
Construct/Operate before installing the engine at your site. The internal
combustion engines must meet AQMD's Best Available Control Technology (BACT)
requirements. BACT for diesel fired emergency back-up engines or for natural gas fired engines can be
d. Rent an engine that has been certified by
the California Air Resources Board (CARB).
CARB has a similar but statewide program to
certify backup generation engines. The use of these CARB certified engines
does not require a permit from the AQMD; however, these statewide registered
portable generators are not to be operated during ISO Stage II or Stage III
alerts, unlike the units permitted by the AQMD. They can only be used for
emergency power generation during actual or imminent blackouts.
Yes, it is possible to obtain a permit for these
engines for more hours provided it complies with the requirements of
Regulation XIII (modeling, offsets, BACT) and Regulation XIV (New Source
Review for Toxics). These applications are handled on a case-by-case basis
and the increased hours of operation granted will also vary based on the
site specific location.
Yes, applications submitted by an emergency
standby generator operator to revise the current permit condition to
increase the allowed hours to the annual maximum of 200 hours as specified
in AQMD's Rule 1110.2 can be approved. However, testing and maintenance
hours are limited, in most cases, to 20 - 50 hours annually pursuant to Rule
To request the change of permit conditions, you
must submit Form 400-A, a copy of the previous permit, and the permit
processing fee. The application to modify the conditions on the permit
will be treated as an Administrative Change in Permit Conditions thereby
qualifying for a reduced fee.
A typical micro-turbine power generation system is
about the size of a refrigerator and generates 30 kilowatts of electricity.
There are larger units that generate 60 kilowatts of electricity. These are
modular units that can be combined to generate more power. The
micro-turbines are normally operated on gaseous fuel (natural gas, propane
or digester gas) and have much lower emissions than diesel fired engines;
however, permits are required if the micro-turbines are fired on landfill
gas, regardless of the size. Permits are not required for the
micro-turbines if the total combined rating is less than 2,975,000 British
thermal units (Btu) per hour.
It is advisable before purchasing any equipment to
consult with the AQMD and apply for approval of a Permit to Construct from
the AQMD to install the engine on your site. Typically, the AQMD either
issues a Permit to Construct or a Permit to Construct/Operate. To obtain a
permit, a permit application must be submitted together with the correct
permit-processing fee. The application package should consist of Form
400-A, Form 400-E-13a and Form 400-CEQA. The forms required for the
Registered/Certified engines are Form 400A, Form 400 CEQA and ICE End-User
The AQMD generally processes a new application for
a Permit to Construct for a backup generator in 2 to 3 months depending on
engineering workload or the complexity of the project. However, the AQMD
permitting staff can work on an overtime basis, if requested by the
applicant, to process the permits in a more expedited manner. These
applications are subject to additional fees as specified in Rule 301(v) and
will also depend on staff availability to work on overtime. To request
expedited processing, please submit Form 400-XPP together with the
application package. This form is available on AQMD's website at
There is a discount of 50% of the permit processing fee for small businesses
(less than 10 employees and with gross income less than $500,000) and a
higher fee of 150% of the permit processing fee for equipment installed and
operated without a permit.
* New fees go into effect
July 1 of each year. Please consult current version of Rule 301 for the
latest fee information.