Consult the quality specifications for gases introduced at the entry points of the Gas System as indicated in Order TED/181/2025.
Natural gas introduced into the gas system, as well as gas returned to ships, shall comply with the following specifications:
Characteristic (*) | Unit | Minimum | Maximum |
|---|---|---|---|
Wobbe index. | kWh/m3 | 13.403 | 16.058 |
PCS. | kWh/m3 | 10.26 | 13.26 |
Relative density. |
| 0.555 | 0.700 |
Total S. | mg/m3 | - | 50 |
H 2 S + COS (as S). | mg/m3 | - | 15 |
RSH (as S). | mg/m3 | - | 17 |
O2. | mol% | - | 0.01 |
CO2. | mol% | - | 2.5 |
H2O (dew point). | oC at 70 bar | - | +2 |
HC (dew point) (**). | oC at 1-70 bar | - | +5 |
Dust / Particles. | - | Technically pure | |
(*) Table expressed under the following reference conditions: [0 °C, V (0 °C, 1.01325 bar)].
(**) LNG has a HC dew point well below the limit values, so it is not measured.
Natural gas transported via an international connection shall comply with the maximum percentage of hydrogen approved in the applicable European regulations, unless otherwise agreed in advance by the parties concerned.
In PCTGs and PCDGs, the biomethane injected shall meet the following specifications:
Characteristic (*) | Unit | Minimum | Maximum |
|---|---|---|---|
Wobbe index. | kWh/m3 | 13.403 | 16.058 |
PCS. | kWh/m3 | 10.26 | 13.26 |
Relative density. |
| 0.555 | 0.700 |
Total S. | mg/m3 | - | 50 |
H 2 S + COS (as S). | mg/m3 | - | 15 |
RSH (as S). | mg/m3 | - | 17 |
| O2. | mol% | - | 0.01 (1) |
CO2. | mol% | - | 2.5 (2) |
H2O (dew point). | oC at 70 bar | - | +2 |
HC (dew point). | oC at 1-70 bar | - | +5 |
| Dust / Particles. | mol % | Technically pure | |
CO. | mol % | - | 0.1 |
H2. | mol % | - | 2% (**) |
| Halogen compounds: Fluoride/Chloride. | mg/m3 | - | 10/1 |
Ammonia. | mg/m3 | - | 10 |
Amines. | mg/m3 | - | 10 |
Mercury. | µg/m3 | - | 1 |
Volatile silicon (as Si). | mg/m3 | - | 0.3 - 1 (***) |
Bencene, toluene, Xylene (BTX). | mg/m3 | - | 500 |
Microorganisms. | - | Technically pure | |
Oil. | - | Technically pure | |
| Other pollutants. | The gas must not contain components other than those specified in this table at levels that prevent its transport, storage and/or use without treatment or quality adjustments. | ||
(*) Table expressed in reference conditions: [0 °C, V (0 °C, 1.01325 bar)].
(**) A 5% mol upper limit may be applied provided that the GTS proves, through hydraulic simulations, that the gas conveyed in the system's facilities and hydrogen-sensitive consumption equipment contains a molar percentage of H2 equal to or less than 2% mol. This same percentage must be complied with in international connections, unless a higher percentage has been agreed upon.
(***) The limit shall be determined in accordance with the criteria set out in Table 1 of UNE-EN 16723-1:2017: Natural gas and biomethane for use in transport and biomethane for injection into the natural gas network. Part 1: Specifications for the injection of biomethane into the natural gas network.
Provided that the water dew point does not exceed −8 °C (at 70 bar), the specifications in the above table may be extended with the following limitations:
– (1) O2: in networks with a pressure less than or equal to 16 bar without reverse flow to transport networks, an upper limit of 1% mol. shall apply. This limit shall also apply to other networks provided that the GTS proves through hydraulic simulations that in O2-sensitive system installations and consumption equipment, such as underground storage facilities and international connections, the gas conveyed contains an O2 percentage equal to or less than 0.01% mol.
– (2) CO2: in networks with a pressure less than or equal to 16 bar without reverse flow to transport networks, an upper limit of 4% mol shall apply. This limit shall also apply in other networks provided that the GTS proves, by means of hydraulic simulations, that in system installations and consumption equipment sensitive to the CO2 limit, such as underground storage facilities and international connections, among others, the gas transported contains a percentage of CO2 equal to or less than 2.5% mol.
Note: At injection points authorised prior to the entry into force of this order, the gas injected may not comply with the specifications set out in this section, provided that it complies with the gas quality regulations in force at the time the injection was authorised. This exception shall not apply to injection capacity extensions requested after the entry into force of this order.
Enagás has obtained Quality Management System certification for its Measurement Process in accordance with the UNE-EN ISO 9001:2000 Standard
