Glossary beginning with P

Pariser Abkommen (see → Paris Climate Agreement)

(Pariser Klimaschutzabkommen) The 21st session of the Conference of the Parties (COP21) to the 1992 United Nations Framework Convention on Climate Change (UNFCCC) took place in Paris in December 2015. It resulted in a global agreement to keep warming well below 2 degrees Celsius above pre-industrial levels – or ideally to pursue efforts to limit the temperature increase to 1.5 degrees above pre-industrial levels. Each nation was responsible for submitting its own Intended Nationally Determined Contributions (INDC) ahead of the conference, outlining the steps it would take to curb its emissions. The EU submitted a single INDC representing all its member states. After the conference, Germany was the first country to set out a policy framework(see → Climate Action Plan 2050) aimed at meeting its goals under the Paris Agreement.

Verursacherprinzip

The polluter pays principle (PPP) is a basic principle of environmental protection, meaning that those who produce pollution should be responsible for its management and, increasingly, clean-up costs. It was enshrined in the Single European Act of 1987. The principle underpins environmental law in many countries, but its interpretations vary. In Germany, it is often referred to in the context of → nuclear decommissioning. It is also increasingly being applied to carbon emissions, with carbon pricing seen as one way of making companies financially responsible for their contribution to global warming.

(Strommarkt 2.0) In June 2016, the German government passed a law to reform the country’s electricity market. Based on an “energy-only market” that exposes the sector to market forces, the government guaranteed that it will not intervene to prevent price peaks – even if the wholesale power price skyrockets at times of scarcity – in order to encourage investment in flexible power stations, load management (see → demand-side management), and →  storage. However, the reform also included provisions to transfer some of the country’s older → lignite power stations into a ’security standby’ to reduce CO₂ emissions. The plants are mothballed for four years, before being closed down permanently. They will only be called upon as a very last resort to ensure security of supply.

(Strommix) The power mix refers to how electricity production and consumption in a country breaks down by primary energy source. It can refer to either power generation, or power consumption, i.e. how much electricity a country uses, taking into account imports and exports. In 2017, renewables covered more than 33 percent of Germany’s gross power generation (or production), and more than 36 percent of its gross power demand (or consumption).
Gross electricity generation usually refers to the total amount of electricity generated in all power plants. Net electricity generation is equal to gross electricity generation minus the amount of power the generating facilities (auxiliary services) use themselves to operate. Gross national electricity consumption includes gross electricity generation minus exports, plus imports. Net national electricity consumption is equal to gross national electricity consumption minus power lost during transmission via the electricity grid.

So far, the shift to renewables in Germany has been largely limited to the power sector. In order to reduce emissions from heating and transport (see → sector coupling), and to enable renewable power to be stored, renewable electricity can be converted into heat or fuels, such as synthetic methane, hydrogen, and liquid fuels. These can be used as “climate-neutral” energy in the heating or transport sectors. Conversion loss remains a major issue. [Read the factsheet on power-to-gas]

(Primärenergieverbrauch) Primary energy mix refers to the different sources of energy a country uses to cover its total energy need. While renewables accounted for about a third of Germany’s electricity generation in 2017, they covered just 13.1 percent of its primary energy consumption, which includes heating and transport (see → sector coupling below). For comparison, renewables covered 13.4 percent of the global primary energy supply in 2015, according to the International Energy Agency.

(Einspeisevorrang) The → Renewable Energy Act (EEG) stipulates that electricity from wind, solar, and biomass gets access to the grid ahead of conventional power. The law also provides that in times of excess supply, conventional power plants must ramp down production. Grid operators must not disconnect wind turbines and solar arrays, unless the stability of the power network is threatened. Additionally, grid operators are obliged to connect new renewable power facilities to the relevant power grid, and if necessary even expand the network to accommodate biomass units, photovoltaics, and wind turbines.

The term prosumer refers to the shift to a distributed energy system (see → decentralised energy), where consumers not only draw power from the grid but also feed it into the grid from home installations, such as rooftop → photovoltaic panels. This poses challenges for the grid, and for the → distribution grid in particular.

(Photovoltaik) Photovoltaic (PV) solar power systems use semiconductors to convert sunlight into electricity. In cooler climates like that in Germany, this is by far the most efficient way to harness the Sun’s energy for the power system (in hotter environments, concentrated solar power that uses the Sun’s heat to generate electricity is also an option). In 2017, photovoltaics – ranging from small, rooftop arrays to huge solar parks – accounted for slightly more than 6 percent of Germany’s power generation.