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Glossary //

Biomethane: Gaseous renewable energy source derived from agricultural biomass (dedicated crops, by-products and agricultural waste and animal waste), agro-industrial (waste from the food processing chain) and the Organic Fraction Municipal Solid Waste (OFMSW).

Bottom-Up: This approach of the scenario building process collects supply and demand data from Gas and Electricity TSOs.

Carbon budget: This is the amount of carbon dioxide the world can emit while still having a likely chance of limiting average global temperature rise to 1.5°C above pre-industrial levels, an internationally agreed-upon target.

CBA: Cost Benefit Analysis carried out to define to what extent a project is worthwhile from a social perspective.

CCS: Carbon Capture and Storage. Process of sequestrating CO2 and storing it in such a way that it won’t enter the atmosphere.

CHP: Combined heat and power

DE: Distributed Energy

DSR: Demand Side Response. Consumers have an active role in the balancing of energy supply and demand by changing their energy consumption according to the energy price and availability. For example by softening demand peaks in case of congestions, or by increasing energy use during surplus supply.

EC: European Commission.

ECI: Energy System Integration Strategy from the European Commission

EVs: Electric vehicles

ENTSOE: European Network of Transmission Operators for Electricity

ENTSOG: European Network of Transmission Operators for Gas

EU27: 27 members of the European Union

ESI: Energy System Integration

ETAG: External Technical Advisory Group

FCEV: Fuel cell electric vehicle

GA: Global Ambition

GHG: Greenhouse gas.

Hybrid Heat Pump: heating system that combines an electric heat pump with a gas condensing boiler to optimize energy efficiency.

ICE: Internal combustion engine

IEA: World Energy Outlook.

Indirect electricity demand: Indirect electrification means electricity demand for production of other energy carriers like hydrogen or synthetic liquids for replacing the use of fossil fuels. Besides industrial processes and hydrogen electrolysis, this could be e.g. heat pumps and electric boilers for district heat production.

IPCC: Intergovernmental Panel on Climate Change

LNG: Liquefied natural gas.

LTS: Long Term Strategy

LULUCF: Land Use, Land Use Change and Forestry. Sink of CO2 made possible by the fact that atmospheric CO2 can accumulate as carbon in vegetation and soils in terrestrial ecosystems.

NECPs: National Energy and Climate Plans are the new framework within which EU Member States have to plan, in an integrated manner, their climate and energy objectives, targets, policies and measures to the European Commission. Countries will have to develop NECPs on a ten-year rolling basis, with an update halfway through the implementation period. The NECPs covering the first period from 2021 to 2030 will have to ensure that the Union’s 2030 targets for greenhouse gas emission reductions, renewable energy, energy efficiency and electricity interconnection are met.

NGO: Non-governmental Organization.

NT: National Trends

NT+: A version of the National Trends scenario which has been adapted to meet the latest EU targets

P2G: Power to gas. Technology that uses electricity to produce hydrogen (Power to Hydrogen – P2H2) by splitting water into oxygen and hydrogen (electrolysis). The hydrogen produced can then be combined with CO2 to obtain synthetic methane (Power to Methane – P2CH4) or can be converted to other energy carriers like for example synthetic ammonia (P2NH3)

P2L: Power to liquids. Combination of hydrogen from electrolysis and Fischer-Tropsch process to obtain synthetic liquid fuels.

P2M: Power to Methane. Creation of methane through the methanation process, where CO2 is combined with H2.

P2X: Aggregation of power to gas and power to liquids.

PCI: Project of Common Interest.

Power-to-Hydrogen/P2Hydrogen: Hydrogen obtained from P2H2.

Power-to-Methane/P2Methane: Renewable methane, could be biomethane or synthetic methane produced by renewable energy sources only.

RES: Renewable energy source.

Synthetic fuel: fuel (gas or liquid) that is produces from renewable or low carbon electrical energy.

TEN-E: Trans-European Networks for Energy, EU policy focused on linking the energy infrastructure of EU countries.

Top-Down: The “Top-Down Carbon Budget” scenario building process is an approach that uses the “bottom-up” model information gathered from the Gas and Electricity TSOs. The methodologies are developed in line with the Carbon Budget approach.

TSO: Transmission System Operator.

TYNDP: Ten Year Network Development Plan.

External Study References //

[1] REGULATION (EU) 2022/869 OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL of 30 May 2022 on guidelines for trans-European energy infrastructure, amending Regulations (EC) No 715/2009, (EU) 2019/942 and (EU) 2019/943 and Directives 2009/73/EC and (EU) 2019/944, and repealing Regulation (EU) No 347/2013

[2] The European Union Agency for the Cooperation of Energy Regulators (2023), Framework Guidelines for the joint TYNDP scenarios to be developed by ENTSO for Electricity and ENTSO for Gas “TYNDP Scenarios Guidelines”

[3] European Commission (2023), National Energy and Climate Plans

[4] European Commission (2023), National long-term strategies

[5] IPCC (2018), Global warming of 1.5°C. An IPCC Special Report on the impacts of global warming of 1.5°C above pre-industrial levels and related global greenhouse gas emission pathways, in the context of strengthening the global response to the threat of climate change, sustainable development, and efforts to eradicate poverty [V. Masson-Delmotte, P. Zhai, H. O. Pörtner, D. Roberts, J. Skea, P.R. Shukla, A. Pirani, W. Moufouma-Okia, C. Péan, R. Pidcock, S. Connors, J. B. R. Matthews, Y. Chen, X. Zhou, M. I. Gomis, E. Lonnoy, T. Maycock, M. Tignor, T. Waterfield (eds.)]. In Press, Figure SPM.3b

[6] Regulation (EU) 2021/1119 of the European Parliament and of the Council of 30 June 2021 establishing the framework for achieving climate neutrality and amending Regulations (EC) No 401/2009 and (EU) 2018/1999 (‘European Climate Law’)

[7] European Commission (2023), National long-term strategies

[8] Eurostat (2023), Share of renewables in gross inland consumption

[9] Ludwig Bölkow Systemtechnik and World Energy Council (2020), INTERNATIONAL HYDROGEN STRATEGIES

Publishing Info //



European Network of
Transmission System Operators for Gas
Avenue de Cortenbergh 100
1000 Brussels, Belgium


European Network of
Transmission System Operators for Electricity
Rue de Spa, 8
1000 Brussels, Belgium


Alexander Kättlitz
David Radu
Joan Frezouls
Laura Lopez
Mads Boesen
Nalan Buyuk

Sub-Team leads of the Joint WG Scenario Building
Joint WG Scenario Building
ENTSOG WG Scenarios
ENTSO-E Regional Groups



DreiDreizehn GmbH, Berlin |

Cover artwork

ZN Consulting, Brussels |


“Introduction”: courtesy of Gas Connect Austria/Monika Aigner
“Scenario Framework”: courtesy of FGSZ
“Scenario Storylines”: courtesy of TenneT/©siemens_ag_ulrich_wirrwa
“Storyline Development”: © allou,

“Input Parameters”: courtesy of GASCADE
“Stakeholder Engagement”: courtesy of GAZ-SYSTEM
“Next Steps”: © vlastas,

Publishing date

July 2023