http://www.legislation.gov.uk/id/eur/2017/460

CHAPTER IIIRESERVE PRICES

Article 12General provisions

1.

For yearly standard capacity products for firm capacity, the reference prices shall be used as reserve prices. For non-yearly standard capacity products for firm capacity, the reserve prices shall be calculated as set out in this Chapter. For both yearly and non-yearly standard capacity products for interruptible capacity, the reserve prices shall be calculated as set out in this Chapter. The level of multipliers and of seasonal factors, set out in accordance with Article 13, and the level of discounts for the standard capacity products for interruptible capacity, set out in accordance with Article 16, may be different at interconnection points.

2.

Where the tariff period and gas year do not coincide, separate reserve prices may be applied respectively:

(a)

for the time period from 1 October to the end of the prevailing tariff period; and

(b)

for the time period from the beginning of the tariff period following the prevailing tariff period to 30 September.

3.

The respective reserve prices published according to Article 29 shall be binding for the subsequent gas year or beyond the subsequent gas year in case of fixed payable price, beginning after the annual yearly capacity auction, unless:

(a)

the discounts for monthly and daily standard capacity products for interruptible capacity are recalculated within the tariff period if the probability of interruption referred to in Article 16 changes by more than twenty percent;

(b)

the reference price is recalculated within the tariff period due to exceptional circumstances under which the non-adjustment of tariff levels would jeopardise the operation of the transmission system operator.

Article 13Level of multipliers and seasonal factors

1.

The level of multipliers shall fall within the following ranges:

(a)

for quarterly standard capacity products and for monthly standard capacity products, the level of the respective multiplier shall be no less than 1 and no more than F11.5;

(b)

for daily standard capacity products and for within-day standard capacity products, the level of the respective multiplier shall be no less than 1 and no more than 3. In duly justified cases, the level of the respective multipliers may be less than 1, but higher than 0, or higher than 3.

2.

Where seasonal factors are applied, the arithmetic mean over the gas year of the product of the multiplier applicable for the respective standard capacity product and the relevant seasonal factors shall be within the same range as for the level of the respective multipliers set out in paragraph 1.

3.

By 1 April 2023, the maximum level of multipliers for daily standard capacity products and for within-day standard capacity products shall be no more than F21.5, if by 1 April 2021 the F3national regulatory authority issues a recommendation F4... that the maximum level of multipliers should be reduced to this level. This recommendation shall take into account the following aspects related to the use of multipliers and seasonal factors before and as from 31 May 2019:

(a)

changes in booking behaviour;

(b)

impact on the transmission services revenue and its recovery;

(c)

differences between the level of transmission tariffs applicable for two consecutive tariff periods;

(d)

cross-subsidisation between network users having contracted yearly and non-yearly standard capacity products;

(e)

impact on cross-border flows.

Article 14Calculation of reserve prices for non-yearly standard capacity products for firm capacity in absence of seasonal factors

The reserve prices for non-yearly standard capacity products for firm capacity shall be calculated as follows:

(a)
for quarterly standard capacity products, for monthly standard capacity products and for daily standard capacity products, in accordance with the following formula:
P_st = (M × T / 365) × D
Where:
- P_st is the reserve price for the respective standard capacity product;
- M is the level of the multiplier corresponding to the respective standard capacity product;
- T is the reference price;
- D is the duration of the respective standard capacity product expressed in gas days.
For leap years, the formula shall be adjusted so that the figure 365 is substituted with the figure 366.
(b)
for within-day standard capacity products, in accordance with the following formula:
P_st = (M × T / 8760) × H
Where:
- P_st is the reserve price for the within-day standard capacity product;
- M is the level of the corresponding multiplier;
- T is the reference price;
- H is the duration of the within-day standard capacity product expressed in hours.
For leap years, the formula shall be adjusted so that the figure 8760 is substituted with the figure 8784.

Article 15Calculation of reserve prices for non-yearly standard capacity products for firm capacity with seasonal factors

1.

Where seasonal factors are applied, the reserve prices for non-yearly standard capacity products for firm capacity shall be calculated in accordance with the relevant formulas set out in Article 14 which shall be then multiplied by the respective seasonal factor calculated as set out in paragraphs 2 to 6.

2.

The methodology set out in paragraph 3 shall be based on the forecasted flows, unless the quantity of the gas flow at least for one month is equal to 0. In such case, the methodology shall be based on the forecasted contracted capacity.

3.

For monthly standard capacity products for firm capacity, the seasonal factors shall be calculated in the following sequential steps:

(a)

for each month within a given gas year the usage of the transmission system shall be calculated on the basis of forecasted flows or forecasted contracted capacity using:

(i)
the data for the individual interconnection point, where the seasonal factors are calculated for each interconnection point;
(ii)
the average data on the forecasted flows or the forecasted contracted capacity, where the seasonal factors are calculated for some or all of the interconnection points.

(b)

the resulting values referred to in point (a) shall be summed up;

(c)

the usage rate shall be calculated by dividing each of the resulting values referred to in point (a) by the resulting value referred to in point (b);

(d)

each of the resulting values referred to in point (c) shall be multiplied by 12. Where the resulting values are equal to 0, these values shall be adjusted to whichever of the following is the lower: F50.1 or the lowest of the resulting values other than 0;

(e)

the initial level of the respective seasonal factors shall be calculated by raising each of the resulting values referred to in point (d) to the same power which is no less than 0 and no more than 2;

(f)

the arithmetic mean of the products of the resulting values referred to in point (e) and the multiplier for monthly standard capacity products shall be calculated;

(g)

the resulting value referred to in point (f) shall be compared with the range referred to in Article 13(1), as follows:

(i)
if this value falls within this range then the level of seasonal factors shall be equal to with the respective resulting values referred to in point (e);
(ii)
if this value falls outside of this range then point (h) shall apply.

(h)

the level of seasonal factors shall be calculated as the product of the respective resulting values referred to in point (e) and the correction factor calculated as follows:

(i)
where the resulting value referred to in point (f) is more than F61.5, the correction factor shall be calculated as F61.5 divided by this value;
(ii)
where the resulting value referred to in point (f) is less than 1, the correction factor shall be calculated as 1 divided by this value.

4.

For daily standard capacity products for firm capacity and within-day standard capacity products for firm capacity, the seasonal factors shall be calculated by carrying out the steps set out in paragraph 3(f) to (h), mutatis mutandis.

5.

For quarterly standard capacity products for firm capacity, the seasonal factors shall be calculated in sequential steps as follows:

(a)

the initial level of the respective seasonal factors shall be calculated as either of the following:

(i)
equal to the arithmetic mean of the respective seasonal factors applicable for the three relevant months;
(ii)
no less than the lowest and no more than the highest level of the respective seasonal factors applicable for the three relevant months.

(b)

the steps set out in paragraph 3(f) to (h) shall be carried out, using the resulting values referred to in point (a), mutatis mutandis.

6.

For all non-yearly standard capacity products for firm capacity, the values resulting from the calculation referred to in paragraphs 3 to 5 may be rounded up or down.

Article 16Calculation of reserve prices for standard capacity products for interruptible capacity

1.

The reserve prices for standard capacity products for interruptible capacity shall be calculated by multiplying the reserve prices for the respective standard capacity products for firm capacity calculated as set out in Articles 14 or 15, as relevant, by the difference between 100 % and the level of an ex-ante discount calculated as set out in paragraphs 2 and 3.

2.

An ex-ante discount shall be calculated in accordance with the following formula:

Di_ex-ante = Pro × A × 100 %

Where:

Di_ex-ante is the level of an ex-ante discount;
Pro factor is the probability of interruption which is set or approved F7by the national regulatory authority pursuant to Article 28, and which refers to the type of standard capacity product for interruptible capacity;
A is the adjustment factor which is set or approved F7by the national regulatory authority pursuant to Article 28, applied to reflect the estimated economic value of the type of standard capacity product for interruptible capacity, calculated for each, some or all interconnection points, which shall be no less than 1.

3.

The Pro factor referred to in paragraph 2 shall be calculated for each, some or all interconnection points per type of standard capacity product for interruptible capacity offered in accordance with the following formula on the basis of forecasted information related to the components of this formula:

$Pro = \frac{N \times D_{int}}{D} \times \frac{{CAP}_{av. int}}{CAP}$

Where:

N is the expectation of the number of interruptions over D;
D_int is the average duration of the expected interruptions expressed in hours;
D is the total duration of the respective type of standard capacity product for interruptible capacity expressed in hours;
CAP_{av. int} is the expected average amount of interrupted capacity for each interruption where such amount is related to the respective type of standard capacity product for interruptible capacity;
CAP is the total amount of interruptible capacity for the respective type of standard capacity product for interruptible capacity.

4.

As an alternative to applying ex-ante discounts in accordance with paragraph 1, the national regulatory authority may decide to apply an ex-post discount, whereby network users are compensated after the actual interruptions incurred. Such ex-post discount may only be used at interconnection points where there was no interruption of capacity due to physical congestion in the preceding gas year.

The ex-post compensation paid for each day on which an interruption occurred shall be equal to three times the reserve price for daily standard capacity products for firm capacity.