Form F4 is used to undertake the annual Self-Assessment of an existing CHP Scheme, described in Form F2, in order to ascertain the portions of its inputs, outputs and capacity that qualify as Good Quality CHP. The Self-Assessment requires:
The period of operation on which Self-Assessment is based
Declaration of energy inputs
Declaration of energy outputs (power)
Declaration of energy outputs (useful heat)
Calculation of CHP Scheme efficiencies
Calculation of CHPQFI, where necessary
Calculation of Quality Index (QI)
Calculation of CHPQPO, where necessary
Calculation of CHPQPC, where necessary
Declaration of exported electricity and heat
F4 is used for all Schemes with TPC 2 MWe or over and for Schemes with TPC <2MWe if boilers are included or if the prime mover is not a reciprocating engine. A simpler form F4S can be used for schemes with installed capacity less than 2 MWe.
Simplified form F4(S) only applies to Reciprocating Engine CHP Schemes that:
are less than 2MWe CHPTPC in size
use only a single conventional fuel e.g. natural gas, diesel
only include a single prime mover, and which is a reciprocating engine, together with associated heat recovery equipment, within the Scheme boundary
do not include heat only boilers
Where Schemes do not meet the Power Efficiency Threshold Criteria for Good Quality CHP the full version of this form (Form F4) must be completed in order to attain certification.
When to complete F4 or F4(S)
Form F4 must be completed annually for each CHP Scheme. Any major change or upgrade to the CHP Scheme, e.g. boundary changes or additional plant, must be notified by submission of a new F2 with an updated line diagram. This should be submitted at the same time as the Self-Assessment Form F4 that covers that year’s performance.
The information provided will be validated by the CHPQA Administrator and forms the basis on which the CHPQA Certificate is issued. CHPQA Certification of new Schemes will be used by Government to assess eligibility for available benefits.
Form F4 or F4(S) is resubmitted each year with scheme performance details for the previous calendar year enabling a new CHPQA certificate to be issued. If there are any significant changes to the scheme (e.g. boundaries, metering) a new Form F2 or F2(S), must also be resubmitted.