The Renewables Obligation (Scotland) Order 2009

Calculating a generating station's renewable output

25.—(1) Subject to article 26, the renewable output of a generating station in any month is equal to–

(a) where the input electricity used by the generating station during that month does not exceed 0.5 per cent of the gross output of that station during that month, A; and

(b) in any other case,

.

(2) In paragraph (1)–

(a) A is equal to

where–

i

C is the gross output of the generating station during the month in question;

ii

D is the energy content of all of the renewable sources used in generating that station's gross output during that month, less the energy content of–

(aa)

any fossil fuel from which those renewable sources are in part composed (other than fossil fuel from which a fuel the energy content of which is deducted by virtue of sub-heads (bb) to (dd) is in part composed);

(bb)

any of those renewable sources which is Solid Recovered Fuel (other than Solid Recovered Fuel which constitutes biomass);

(cc)

any of those renewable sources which is a liquid fuel produced by means of pyrolysis and which has a gross calorific value when measured at 25 degrees Celsius and 0.1 megapascals at the inlet to the station of less than 10 megajoules per metre cubed; and

(dd)

except in the case of an excepted generating station, any of those renewable sources which is a gaseous fuel produced by means of gasification or pyrolysis and which has a gross calorific value when measured at 25 degrees Celsius and 0.1 megapascals at the inlet to the station of less than 2 megajoules per metre cubed;

iii

E is the energy content of all of the fuels used in generating that station's gross output during that month;

(b) B is the gross output of that station during that month less the input electricity it uses during that month.

(3) Subject to paragraph (4), where during any month the renewable output of a generating station is generated in two or more ways and the amount of electricity to be stated in each SROC issued in respect of that renewable output is not always the same (because the amount of electricity to be stated in SROCs issued in respect of electricity generated in one or more of those ways differs from the amount to be stated in SROCs issued in respect of some or all of the remaining electricity by virtue of articles 27 to 32), the proportion of the station's renewable output which, for the purposes of those articles, is generated in each of those ways is F ÷ G where–

(a) F is the energy content of the renewable sources used when generating electricity in that way during that month less the energy content of–

(i) any fossil fuel from which those renewable sources are in part composed (other than fossil fuel from which a fuel the energy content of which is deducted by virtue of heads (ii) to (iv) is in part composed);

(ii) any of those renewable sources which is a Solid Recovered Fuel (other than Solid Recovered Fuel which constitutes biomass);

(iii) any of those renewable sources which is a liquid fuel produced by means of pyrolysis and which has a gross calorific value when measured at 25 degrees Celsius and 0.1 megapascals at the inlet to the station of less than 10 megajoules per metre cubed; and

(iv) except in the case of an excepted generating station, any of those renewable sources which is a gaseous fuel produced by means of gasification or pyrolysis and which has a gross calorific value when measured at 25 degrees Celsius and 0.1 megapascals at the inlet to the station of less than 2 megajoules per metre cubed; and

(b) G is the energy content of all of the renewable sources used in generating that generating station's gross output during that month less the energy content of–

(i) any fossil fuel from which those renewable sources are in part composed (other than fossil fuel from which a fuel the energy content of which is deducted by virtue of heads (ii) to (iv) is in part composed);

(ii) any of those renewable sources which is Solid Recovered Fuel (other than Solid Recovered Fuel which constitutes biomass);

(iii) any of those renewable sources which is a liquid fuel produced by means of pyrolysis and which has a gross calorific value when measured at 25 degrees Celsius and 0.1 megapascals at the inlet to the station of less than 10 megajoules per metre cubed; and

(iv) except in the case of an excepted generating station, any of those renewable sources which is a gaseous fuel produced by means of gasification or pyrolysis and which has a gross calorific value when measured at 25 degrees Celsius and 0.1 megapascals at the inlet to the station of less than 2 megajoules per metre cubed.

(4) In any month where a generating station generates some or all of its renewable output using mixed gas, the proportion of the station's renewable output which is, for the purposes of articles 27 to 31–

(a) generated using mixed gas in the way described as “AD” in Schedule 2 is

;

(b) generated using mixed gas in the way described as “electricity generated from sewage gas” in that Schedule is

.

(5) In paragraph (4)–

(a) H is the energy content of the mixed gas used when generating the generating station's renewable output during the month in question;

(b) I is the energy content of all of the renewable sources used in generating that station's renewable output during that month;

(c) J is the dry mass of–

(i) any waste which constitutes a renewable source (other than sewage); and

(ii) any biomass (other than sewage),

from which the mixed gas used in generating that station's renewable output during that month is formed, less the dry mass of any digestible fossil fuel from which that waste or biomass is in part composed;

(d) K is the dry mass of the sewage from which the mixed gas used in generating that station's renewable output in that month is formed; and

(e) L is the dry mass of all of the material from which the mixed gas used in generating the station's renewable output during that month is formed, less the dry mass of any digestible fossil fuel from which that material is in part composed.

(6) In this article–

“dry mass”, in relation to a fuel, means the mass of the fuel when any water present in it has been removed;

“excepted generating station” means a generating station–

(a)

which is accredited on or before 31st March 2011;

(b)

which, since being accredited, has not ceased to be accredited at any time; and

(c)

in respect of which, if it was not accredited as at 31st March 2009, preliminary accreditation was held on and from that date until the date on which it was accredited;

“gross output”, in relation to a generating station, means the total amount of electricity generated by that station;

“input electricity” has the same meaning as in article 24; and

“mixed gas” means gas formed by the anaerobic digestion of sewage together with–

(a)

waste which constitutes a renewable source (other than sewage); or

(b)

biomass (other than sewage).