Geothermal Energy: a glimpse at the state of the field and an introduction to the journal

Abstract

© A m Editorial We enthusiastically present to you this new journal dedicated solely to the growing field of geothermal energy and the many aspects and issues surrounding it. Geothermal Energy is a peer-reviewed, open-access journal published by SpringerOpen, providing a forum for geothermal research and investigating the opportunities and challenges of geothermal resources in both deep and shallow systems. A holistic view into geothermal energy in combination with the open-access concept makes this journal unique as new knowledge is provided efficiently and without barriers from and to the scientific community. Since the Fukushima nuclear disaster in March 2011, the discussion around future energy resources and supply has permeated all levels of society. A new energy paradigm is evolving, in which renewable resources are increasingly gaining attention in science, technology, economics, safety, and public acceptance. Geothermal energy is a promising alternative energy source as it is suited for baseload energy supply, can replace fossil fuel power generation, can be combined with other renewable energy sources such as solar thermal energy, and can stimulate the regional economy. While disturbance of the land surface is small in the procuration of geothermal energy, questions remain as to the impact of subsurface activities on the greater region. To bring geothermal energy to a level in which it can be truly integrated into a nation’s energy palette, more research is necessary in the fields of geotechnical engineering, natural sciences, and socioeconomics. For the safe, long-term operation of deep geothermal systems, we require a better understanding on the functioning of the geological subsurface and its changing thermal, hydraulic, mechanical, and biogeochemical conditions. Access to geothermal reservoirs by drilling remains costly and associated with high exploration risks. Hydraulic stimulation is often necessary, turning deep subsurface reservoirs into efficient heat exchangers, i.e., enhanced or engineered geothermal systems (EGS). Even though several geothermal research projects have been conducted or are underway and power plants are in operation, the understanding we have about EGS is still based on the lessons learned from a few long-term sites. Shallow geothermal systems have long been the focus of engineering development. In Germany alone, about half a million heat pumps have been installed. Current research on shallow systems focuses on optimization and environmental impacts. For example, geothermal heat pumps are normally installed without detailed knowledge of