What are some hydropower generation methods

Renewable energies - the way to the future

Climate protection is not the only reason to promote the expansion of renewable energy sources. Fossil fuels - so far the most important source of energy for humankind - are only available to a limited extent. While great efforts are being made to develop new deposits, the reserves will in all likelihood be sufficient until the end of the century at the most. In addition, fossil fuels can only be found in certain places, whereas regenerative energy sources are available all over the world. In this way, a country can - at least in theory - be completely self-sufficient with renewable energies.

However, the undeniable advantages of regenerative energies are also countered by a number of problems. The expansion is sometimes associated with high costs, and the assessment of the benefits for the climate and the environment of the individual production methods is controversial.

What are renewable energies?

Renewable or regenerative energies are energy sources that, in principle, have a unlimited time available stand. The term has become common to differentiate these energy sources from fossil fuels such as oil and natural gas, because the global reserves of coal, oil and gas are finite and only regenerate over a period of millions of years.

Renewable energies generally include Water and wind power, solar radiation and geothermal energy. Renewable raw materials, such as wood for pellet production or rapeseed for biodiesel, regenerate very quickly and are therefore also counted as renewable energies.

The fact that renewable energies are practically “endless” has led to the widespread assumption that they are also available in unlimited quantities. In fact, this is not correct, because the sun, wind and water only provide a certain amount of energy - although this is far above the current global demand.

Tip: How can I use renewable energies?

By opting for renewable energies, you as a customer can set an example for climate and environmental protection - but what options do you actually have for use? The green electricity tariff with the electricity provider is certainly a very obvious variant, but there are more ways:

  • Installation of a pellet heating system or a geothermal heat pump in the house
  • Use of biodiesel as a fuel
  • Installation of a photovoltaic system on the house roof
  • Conclusion of a green electricity tariff
  • Use of power plants or environmental funds as a financial investment

Use of renewable energies in an international comparison

The advancing climate change has become one Rethinking politics not only in industrialized countries, but also in developing and emerging countries. The amount of energy generated by regenerative energy sources increased by around 100 percent between 2004 and 2013, and in 2012 it was possible to use renewable energies 19 percent of the world's energy needs are covered.

The fact that environmentally friendly energy generation has gained in importance is also shown by the number of countries that have made the promotion of renewable energies an important political goal. While there were 55 countries in 2005, the number had grown to 138 by 2014, including 95 developing and emerging countries. The latter is interesting insofar as in economically up-and-coming countries, environmental policy goals usually lagged behind economic development in the past. In the meantime, however, climate policy - at least officially - has a similar status to economic development.

Particularly noteworthy in this context is China, currently the largest producer of climate-damaging carbon dioxide. Here, the share of renewable energies is to be increased by 50 percent by 2017 - compared to the 2013 figure. If this ambitious goal is implemented, the share of renewables in electricity generation would rise from almost 30 to around 45 percent - an international record.

Despite lofty goals, the Use of renewable energy sources in many countries is still in its infancy. This is no different within the EU - in a global comparison, the EU as a whole, with a share of 14.1 percent for renewables in 2012, is even below the average.

However, there are some countries in which a significantly higher proportion is achieved. In 2012 the EU front runners were:

  • Sweden (51%)
  • Latvia (35.8%)
  • Finland (34.3%)
  • Austria (32.1%)

Situation in Germany

In 2012, Germany had a share of energy consumption of 12.4 percent for renewable energies and was thus in the middle of the range of EU countries. If you only look at the electricity market and not the entire energy market, Germany comes to a much better value: In 2012, a good 23 percent of German electricity demand was covered by renewable energy sources, in 2013 it was already around 25 percent.

The generation of energy from biomass made up by far the largest share of renewable energies in 2013 at around 50 percent. This was followed by wind power (15 percent), photovoltaics (9 percent), biodiesel (7 percent) and hydropower (6 percent). If we look at power generation alone, 34 percent is accounted for by wind power, 27 percent by biomass, 19 percent by photovoltaics and 14 percent by hydropower.

The massive increase in regenerative energies in Germany is due not least to the “Law for the Expansion of Renewable Energies” (also known as the “Renewable Energies Act” or “EEG” for short).

The forerunner, the “Law on Feeding Electricity from Renewable Energy into the Public Grid”, stipulated as early as 1991 that electricity from renewable energy sources should preferably be fed into the electricity grid - and that the producers receive a fixed feed-in tariff. Since this feed-in tariff, which varies depending on the electricity generation method and the year of construction of the system, is usually significantly higher than the electricity price on the market, green electricity can also be produced profitably and is therefore an interesting investment area.

Although the EEG has weak points and individual points are repeatedly discussed controversially, overall it is considered - also from an international perspective - as a successful model for promoting renewable energies.

Future funding in Germany

Until now, producers hardly had to worry about profitability when producing electricity from renewable energy sources - thanks to the high feed-in tariffs, profitable operation was almost always achievable. This promotion made possible the so-called "EEG surcharge", which every electricity customer has to pay for every kilowatt hour consumed, regardless of the source from which his electricity comes. Since more and more electricity was produced with the help of regenerative energy sources, the subsidy continued to rise - and with it the EEG surcharge.

In order to counteract the rising electricity prices, the federal government decided 2014 an amendment to the EEG. Among other things, the feed-in tariffs were reduced and so-called “expansion corridors” were resolved, and a “breathing lid” was set for various generation methods.

The expansion corridors regulate the amount of electricity to be produced by a certain point in time (around 2020 or 2030) with the help of the generation methods. This serves to control the expansion, but critics criticize certain expansion targets, such as lowering the target for offshore wind power. The breathing lids concern the feed-in tariffs. If a method such as wind power is used to produce electricity up to the targeted amount, the feed-in tariff remains unchanged. However, if the amount of electricity produced exceeds the target value, the remuneration is reduced.

The innovations in the EEG are not only intended to result in the Electricity prices stable being held. Renewable energies are also supposed to focus more on this Put competition in the market, because the ultimate goal of the funding is environmentally conscious and at the same time economical electricity production. Critics of the innovations mainly complain about the cuts in bioenergy, because thanks to the storage capacity of biomass, it serves as a compensation for weather-dependent electricity production through wind and solar power.

The extent to which the amendment to the EEG will affect the expansion of renewable energies cannot yet be estimated, but it is certain that it will slow down significantly in some areas.

Evaluation of renewable energies

With the promotion of renewable energy sources, criticism also arose at the same time. Among other things, the actual benefits for the environment were questioned, and critics repeatedly refer to the high costs of generating electricity from renewable energy sources. That Renewable energies relieve the environment and climate, has meanwhile been proven in numerous studies.


Thanks not least to the funding, the technology has now advanced to such an extent that the systems can be amortized in terms of energy without any problems within their useful life - that is, they produce more energy during their entire operation than was used to generate them. The effects on the immediate vicinity of the systems have also been mitigated by technical innovations. For example, a minimum distance to inhabited areas is prescribed for wind turbines, and the rotor blades are coated with a non-reflective layer. This eliminates annoyance from noise and reflections from the sun.

Unsolved problems

Despite the progress, there are still unsolved problems with renewable energies. Large areas are flooded by dams or dams, for example, which in some cases results in massive changes in the ecosystem. Nevertheless, renewable energies are much safer than fossil fuels with regard to the climate and the environment.


In the The various production methods differ in terms of economic efficiency very strong. Hydropower is considered to be the cheapest form of energy generation - in terms of economic efficiency, it even surpasses electricity generation using coal and gas. Even modern onshore wind turbines can keep up with conventional electricity generation in terms of costs, provided they are in a favorable location. In terms of economic efficiency, photovoltaic systems are roughly on par with gas-fired power plants, but not with coal-fired power plants. Offshore wind farms, biogas plants and geothermal power plants are generally less economical than conventional power plants.

In this consideration, however, only the direct costs of electricity generation are included - external costs are not taken into account. This term "external costs" comes from economics and describes the costs that arise from the social use of a technology or a product. In the case of energy generation, these are primarily costs caused by damage to the environment, climate and health. Possible examples of costs or damage would be respiratory diseases caused by fine dust from coal-fired power plants, storage costs for fuel rods from nuclear power plants or costs for the resettlement of residents when building a dam.

Good to know: It is relatively difficult to determine external costs exactly

According to a study by the Federal Environment Agency in 2007, the external costs for conventional energy sources are between 4 and 8 cents per kilowatt hour, while regenerative energy sources come to 0.1 to 1 cents per kilowatt hour. Since these values ​​are disregarded in most of the considerations, the picture of the profitability of electricity generation is clearly distorted to the detriment of regenerative energies.

If one includes the societal costs, are Renewable energy sources are superior to conventional ones in terms of environmental and climate protection as well as economic efficiency.

Prospects for renewable energies

The long-term goal of environmental and energy policy in Germany is one Full supply through regenerative energies. The only question is: how realistic is this goal?

Theoretically, a full supply is easily possible, because the solar radiation over Germany alone provides a hundred times the German demand for energy. Ultimately, then, it is a matter of political will whether the goal can be achieved or not.

With the final phase-out of nuclear energy and the EEG, the course has certainly been set correctly; other measures must now follow. In industry in particular, but also in private households, energy efficiency must be increased and electricity consumption reduced. In addition, renewable energies have to be continuously developed and expanded. This process will certainly still be take many years to completeIn addition, Germany depends on partners to ensure a continuous and secure power supply at all times. In 2020, renewables are expected to cover around 47 percent of the electricity demand in Germany, so there is still a long way to go before they are fully supplied.

The development towards renewable energies is not limited to Germany, in many other countries too Expansion pushed ahead with high pressure. In emerging and developing countries in particular, however, it is not only the effects on the climate and the environment that play a role. Fossil fuels often make up between 20 and 40 percent of the cost of all imports in these countries. Renewable energy makes the states less dependent on the international gas and oil market and also improves their trade balance.

Despite the increasing importance of renewable energies, an international climate protection agreement that prescribes fixed and resilient climate protection goals and thus sets the course for the energy transition worldwide is still a long way off. As has been shown time and again, the states can only agree on a minimal consensus at the UN climate conferences - the ideas and priorities are too different.

It is left to individual states like Germany to take on a pioneering role in terms of climate protection in the hope that other countries will follow suit.