Certainly, although today hydropower is by far the major contributor to overall renewable power in the region - currently supplying something more than 60% of the total renewable-generated electricity - the prospects for growth in Europe are not considered to be in the same league as those of other renewable energy technologies, such as wind, solar and bioenergies.

There are a number of reasons for this perception. For example, European planning and environmental conditions make large-scale inundations all but impossible, and there is of course the fact that most of the best resources and sites have been developed already.

This is perhaps why hydro, with the notable exceptions of ocean wave and tidal and small/micro-scale development, has been largely excluded from renewable energy policy debate and consequently the legislation designed to foster growth in the sector.

However, while hydropower appears to be absent from the many existing support mechanisms designed to engender the accelerated development of renewable energy, the rapid ramp up of variable output renewable technologies such as wind and solar is nonetheless providing some major opportunities for hydroelectricity.

It is well known that one of the major issues to be overcome with regard to integrating large volumes of renewable energy generating capacity into the grid is that of variability. And it is also well known that pumped-storage hydropower is currently the only widespread, commercially available technology able to the offer large-scale storage that is required to achieve Europe's renewable energy policy goals. Let's not forget that the EU has set an ambitious target of achieving 20% of its total energy requirements from renewable energy by 2020. Current best estimates suggest that in order to achieve this, at least 30% of the Union's electricity will have to come from renewable energy sources by then. Clearly then, there is an obvious symbiosis between those technologies destined for stratospheric growth by dint of policy directives and those by dint of practical expediency. Equipped with large storage capacities, rapid start-up and clean credentials, pumped storage solves a number of integration issues at a stroke.

Furthermore, a recent study conducted by the Joint Research Centre of the European Commission together with the Sustainable Energy Research Group at University College Cork found that there are indeed opportunities for such development in Europe. In the study, titled "Pumped-hydro Energy Storage: Potential for Transformation from Single Dams," authors Roberto Lacal Arantegui, Niall Fitzgerald and Paul Leahy argue that, compared with the high environmental and social impact of most new hydropower plant developments in Europe, the transformation of an existing reservoir into a pumped hydro system offers the prospects of a much smaller impact.

It's no coincidence that some of these themes are explored in our lead feature, which considers the significant opportunities available for new hydropower developments in Europe - not least from the burgeoning requirement for a European-wide ancillary services market. And while pumped-storage development may yet offer the best prospects for hydro development in Europe, there are still opportunities for other types of large-scale hydro. Another of our features in this edition takes a look at the 100 MW Glendoe hydro project in Scotland, which was first commissioned just a few years ago in late 2008 and is now due to be restarted any day after extensive repairs in the wake of a tunnel rockfall.

Of course, unmissable in this edition is our worldwide buyers' guide and directory, published annually. This invaluable addition details the global hydropower industry as well as trade groups, organizations, services companies and equipment manufacturers and suppliers - presenting contact details and areas of expertise. To be included in next year's directory, contact the HRW-Hydro Review Worldwide editors at hydroreview@pennwell.com.

Overall then, it seems that despite some negative perceptions, there are indeed significant new opportunities for the development of large scale hydro in Europe. Opportunities which are generated by the wider push towards a low-carbon future, even though large hydro does not, at face value, particularly benefit from such policy support. It seems also that much of this development can be delivered both economically and with low social and environmental impacts.

And, with the buyers' guide in this edition, now you'll know who to call.