The Guarantees of Origin of Electricity Produced from High-efficiency Cogeneration Regulations (Northern Ireland) 2008

Regulation 2 and paragraph 5 and 6 of Schedule 2

[F1 SCHEDULE 3 N.I. Methodology for determining the efficiency of the cogeneration process

Textual Amendments

F1 Schs. 2-4 inserted (31.12.2020) by The Guarantees of Origin of Electricity Produced from High-efficiency Cogeneration (Amendment) (EU Exit) Regulations 2018 (S.I. 2018/1206), regs. 1(3), 4(7); 2020 c. 1, Sch. 5 para. 1(1)

Values to be used N.I.

1.   Values used for calculation of efficiency of cogeneration and primary energy savings must be determined on the basis of the expected or actual operation of the unit under normal conditions of use.

High-efficiency cogeneration N.I.

2.   For the purposes of these Regulations high-efficiency cogeneration shall fulfil the following criteria—

(a) cogeneration production from cogeneration units shall provide primary energy savings, calculated in accordance with paragraph 3, of at least 10% compared with the references for separate production of heat and electricity;

(b) production from small-scale and micro-cogeneration units providing primary energy savings may qualify as high-efficiency cogeneration.

Calculation of primary energy savings N.I.

3.   The amount of primary energy savings provided by cogeneration production defined in accordance with Schedule 4 must be calculated on the basis of the following formula—

where—

PES is primary energy savings;

CHP Hη is the heat efficiency of the cogeneration production defined as annual useful heat output divided by the fuel input used to produce the sum of useful heat output and electricity from cogeneration;

Ref Hη is the harmonised efficiency reference value for separate heat production;

CHP Eη is the electrical efficiency of the cogeneration production defined as annual electricity from cogeneration divided by the fuel input used to produce the sum of useful heat output and electricity from cogeneration. For the purpose only of calculating the electrical efficiency of the cogeneration production, where a cogeneration unit generates mechanical energy, the annual electricity from cogeneration may be increased by an additional element representing the amount of electricity which is equivalent to that of mechanical energy;

Ref Eη is the harmonised efficiency reference value for separate electricity production.

Calculations of primary energy savings using alternative calculation N.I.

4.— (1) The competent authority may calculate primary energy savings from a production of heat and electricity and mechanical energy in accordance with sub-paragraph (2) without applying Schedule 4 to exclude the non-cogenerated heat and electricity parts of the same process. Such a production can be regarded as high-efficiency cogeneration provided it fulfils the efficiency criteria in paragraph 2 and, for cogeneration units with an electrical capacity larger than 25 megawatts (MW), the overall efficiency is above 70%. However, specification of the quantity of electricity from cogeneration produced in such a production, for issuing a guarantee of origin, must be determined in accordance with Schedule 4.

(2) If primary energy savings for a process are calculated using the alternative calculation in sub-paragraph (1) the primary energy savings must be calculated using the formula in paragraph 3 but replacing “CHP Hη” with “Hη” and “CHP Eη” with “Eη”, where—

• Hη means the heat efficiency of the process, defined as the annual heat output divided by the fuel input used to produce the sum of heat output and electricity output;

• Eη means the electricity efficiency of the process, defined as the annual electricity output divided by the fuel input used to produce the sum of heat output and electricity output. For the purpose only of calculating the electrical efficiency of the cogeneration production, where a cogeneration unit generates mechanical energy, the annual electricity from cogeneration may be increased by an additional element representing the amount of electricity which is equivalent to that of mechanical energy.

5.   The competent authority may use other reporting periods than one year for the purpose of the calculations according to paragraphs 3 and 4. N.I.

6.   For micro-cogeneration units the calculation of primary energy savings may be based on certified data. N.I.

Efficiency reference values for separate production of heat and electricity N.I.

7.— (1) The harmonised efficiency reference values consist of a matrix of values differentiated by relevant factors, including year of construction and types of fuel, and must be based on a well-documented analysis taking, inter alia, into account data from operational use under realistic conditions, fuel mix and climate conditions as well as applied cogeneration technologies.

(2) The efficiency reference values for separate production of heat and electricity in accordance with the formula set out in paragraph 3 establish the operating efficiency of the separate heat and electricity production that cogeneration is intended to substitute.

(3) The efficiency reference values must be calculated according to the following principles—

(a) for cogeneration units the comparison with separate electricity production must be based on the principle that the same fuel categories are compared;

(b) each cogeneration unit must be compared with the best available and economically justifiable technology for separate production of heat and electricity on the market in the year of construction of the cogeneration unit;

(c) the efficiency reference values for cogeneration units older than 10 years of age must be fixed on the reference values of units of 10 years of age;

(d) the efficiency reference values for separate electricity production and heat production must reflect the climate of the United Kingdom.]