Power to liquid and power to gas: An option for the German Energiewende

Abstract

The large-scale deployment of renewable energy sources (RES) is an important aspect of decarbonising the energy supply, and represents a key part of the German Energiewende. However, significantly increasing the share of renewable power in the energy mix implies coping with the natural intermittency of RES like wind and solar. RES development also does not directly address non-electric energy needs such as fuels for transportation and industry feedstock, which are presently relying on fossil fuels. Therefore, the conversion of surplus renewable electricity (RES-E) into the more convenient form of a liquid or gas (power-to-liquid and power-to-gas) could help offset RES intermittency while providing a diverse mix of energy carriers. If recycled CO 2 is used in the fuel synthesis process, overall emissions can be greatly reduced. This paper aims to sketch the possible contribution of RES-E combined with power-to-gas (PtG) and power-to-liquid (PtL) schemes in the 2050 German energy system, by modelling an increase in installed renewable power. Different scenarios are laid out and compared, and the results are utilised in a basic economic assessment of the fuel production cost for an hypothetical power-to-liquid plant.

Optimization through Response Surface Methodology of a Reactor Producing Methanol by the Hydrogenation of Carbon Dioxide

“…Global energy demand is expected to double by 2050 [1]. More than 80% of global energy demand is still satisfied by fossil fuels due to their abundance and availability [2].…”

The Potential for Electrofuels Production in Sweden Utilizing Fossil and Biogenic CO2 Point Sources

“…This can be compared to the CO2 capture cost linked to processes requiring an extra purification step like steel and iron, ammonia, refinery, cement, and fossil or biomass combustion plants estimated at 20€2015-170€2015/ ton CO2 in the short term (10-15 years) and 10€2015-100€2015/ton CO2 in the more long term (Damen et al, 2007;Finkenrath, 2011;Kuramochi et al, 2012Kuramochi et al, , 2013IEA, 2013). Even though it has been indicated that the cost for carbon capture represents a relatively modest share (a few percent) of the total electrofuel-production cost unless air capture is assumed (Graves et al, 2011;Tremel et al, 2015;Varone and Ferrari, 2015; see text footnote 1), using CO2 from biofuel production represent an attractive source for electrofuel production since more pure streams will likely be used first for economic reasons and the domestic biofuel actors, representing a considerable biofuel production capacity, in order to comply with sustainability requirements need to improve their production processes in terms of CO2 emissions. Table 1 presents the type of CO2 stream, typical concentration of CO2, the range of CO2 emissions per unit, and the amount of recoverable CO2, for different point sources.…”

“…Interest in electrofuels is on the rise, both in the literature (Graves et al, 2011;Mohseni, 2012;Nikoleris and Nilsson, 2013;Taljegård et al, 2015) 1 and in terms of demonstration plants in the EU, in some cases, including CO2 capture (Gahleitner, 2013). Studies mainly investigate electrofuels as a (i) technology for storing intermittent electricity [e.g., Streibel et al (2013), de Boer et al (2014, Vandewalle et al (2014), König et al (2015), Qadrdan et al (2015), Varone and Ferrari (2015), Zakeri and Syri (2015), Zhang et al (2015), and Kötter et al (2016)], (ii) fuel for transport [e.g., Connolly et al (2014), Ridjan et al (2014), Larsson et al (2015)], or (iii) means of producing chemicals [e.g., Ganesh (2013), Perathoner and Centi (2014), and Chen et al (2016)]. Different types of energy carriers [e.g., methane, methanol, DME (dimethyl ether), gasoline, and diesel] can be produced, which makes electrofuels a potentially interesting option for all transport modes, especially shipping, aviation, and long distance road transport, where the potential for other renewable fuel options, such as electricity and hydrogen, may be limited.…”

Power-to-gas technology in energy systems: current status and prospects of potential operation strategies

“…The value of C M varies depending on the sources of carbon dioxide, and the expenditure for carbon dioxide approximately ranges from 10 $/t to 1000 $/t, and the coefficient a is approximately 0.2 t/MWh [8,18,27]. Figure 2 compares the income, revenue and cost compositions of PtG plants with C M price at 10 $/t (e.g.…”

“…The cost of carbon sources also becomes nonnegligible with the increase of C M . The cost of carbon dioxide is somewhat very complicated to quantify and out of the scope of this paper [27]. Thus, the influences of C M will be omitted and no further discussions will be included in the rest part of this paper.…”