When to consume electricity? View from cost and carbon emission: case in Germany

Paper i proceeding, 2016

In Germany, the share of renewable variable energy sources, such as wind and solar, has greatly increased in the recent decade: from less than 1% in 1990 to 20% in 2015. Due to its fluctuating availability, the share of the renewables in the electricity mix changes over the time of day throughout the years. This results in a fluctuation of electricity prices and the associated carbon emission factors. The paper conducted a Life Cycle Assessment (LCA) on the German electricity based on hourly data for 2015 taken from the EEX database. In 2015 the minimum and maximum hourly carbon emission factor deviated by more than threefold. This highlights the relevance of the time of electricity consumption for assessing the carbon emission correctly in the German setting. The same was found to hold true for economic costs as well. The electricity price traded in EPEX spot market ranged from negative values to over 100 Euro per MWh. Observing such fluctuation, the study analyzed the correlation of hourly electricity price on the spot market and the hourly carbon emission factor of Germany in 2015. The study showed positive correlation between the price and emission factor (r = 0.65), indicating that within this framework cost savings and emission reduction tend to go hand in hand. The paper includes the potential effect of the findings on different consumers under conditions which apply a higher time resolution on billing as well as environmental reporting. Consumers such as cooling in residential and office setting were found to be overrated in established schemes and may profit economically from real time billing. Consumers such as industry and energy efficient housing were underrated in terms of emissions and would suffer from real time billing.