Can renewable energy sources power the world?
Can renewable energy sources power the world?

Start this free course now. Just create an account and sign in. Enrol and complete the course for a free statement of participation or digital badge if available.

2.2 National hydro resources

Data for the 11 countries whose hydro output in 2015 was greater than 50 TWh, together with a few other European countries of interest is shown in Table 2. Several countries appear to have developed more than half their technical potential already; but some may limit their estimates of ‘technical potential’ to sites that have been studied in detail.

Table 2 National hydro potential and contributions, 2015 (sources: WEA, 2010a, BP, 2010)
CountryTechnical potential/TWh y-1Installed capacity/GWAnnual output/TWh y-1Average capacity factorPercentage of nation’s electricity

The countries with the highest capacity factors tend to be those where hydropower makes a significant contribution but is not the only major source of electricity – a situation that allows the relatively cheap hydropower to be used to its full potential, with an alternative source of electricity available when hydropower cannot meet demand.

In general, if almost all a nation’s electricity comes from hydro plants, annual capacity factors are usually lower, because the installed capacity must be large enough to meet the maximum demand experienced during any day (or year).

Compared with the countries in Table 5.2, the hydro resource of the UK is small. The installed capacity in 2016 was about 1.8 GW including a little over 350 MW small-scale hydro, (BEIS, 2017) with output varying in recent years between about 4.7 and 6.3 TWh – reflecting year-on-year weather variations throughout this relatively small area. However the capacity of and production from small scale hydroelectric plants has shown as significant increase in recent years from 216 MW in 2012 to over 350 MW in 2016 (BEIS, 2017).

Watch this short video, which describes the 152.5MW Loch Sloy hydroelectric power station and gives a brief view of small-scale hydro installation.

Download this video clip.Video player: scottish_hydro_hq_640.mp4
Interactive feature not available in single page view (see it in standard view).

Next you’ll look at hydro output on a world scale.

Take your learning further

Making the decision to study can be a big step, which is why you'll want a trusted University. The Open University has 50 years’ experience delivering flexible learning and 170,000 students are studying with us right now. Take a look at all Open University courses.

If you are new to University-level study, we offer two introductory routes to our qualifications. You could either choose to start with an Access module, or a module which allows you to count your previous learning towards an Open University qualification. Read our guide on Where to take your learning next for more information.

Not ready for formal University study? Then browse over 1000 free courses on OpenLearn and sign up to our newsletter to hear about new free courses as they are released.

Every year, thousands of students decide to study with The Open University. With over 120 qualifications, we’ve got the right course for you.

Request an Open University prospectus371