What is the best source of clean energy

Strategies for the future

In order to have enough affordable energy available in the future without unduly polluting the environment when it is generated, the focus is on two strategies: better use of energy and the replacement of fossil fuels with renewable energies. The better use of energy is the important first step, as it is usually cheaper than tapping new energy sources, and any type of energy generation pollutes the environment.

The importance of a reliable energy supply for our quality of life can hardly be overestimated; However, the current system of energy supply is also a major contributor to air pollution and climate change; and whether energy will remain affordable in the future is more than uncertain in view of the finite nature of fossil fuels (>> example oil)). What needs to be considered if we want to make our energy supply fit for the future was already described by an expert committee of the federal government in 2003:

Guard rails for sustainable energy policy

A sustainable energy supply is not allowed Air pollution cause that makes people sick or to one Climate change that is more than 2 ° C (whereby the latter value is not a desirable target, but a realistic minimum damage; less is considered hardly possible - see also >> How can we end climate change?). The cultivation of bioenergy crops is allowed not at the expense of food supplies and must not happen at the expense of natural ecosystems - therefore no more than 3 percent of the world's land area may be used for this. Sustainable energy supply should be one Access to modern energy systems for all people in the world, and it should no intolerable risks cause.

(from the report “Energy turnaround for sustainability” of the German Advisory Council on Global Change, page 115)

Any energy generation, including that from renewable energy sources, pollutes the environment. The differences between the energy sources are enormous, but the following still applies: the cleanest energy is that that does not have to be generated - and there is huge potential here: the majority of the energy generated is >> not used at all. Before the question of future energy sources, the question should therefore be how much energy we actually need.

The efficiency strategy

Reduce conversion losses:
Efficient power generation and combined heat and power

Electricity generation in thermal power plants is particularly lossy, with which on average only about 39 percent of the primary energy is used. Modern power plants can achieve efficiencies of up to 53 percent, but the problem is a fundamental one: Electricity is a high-quality energy source (see box >> Energy: Quality counts as well as quantity), the production of which in thermal power plants is always associated with considerable heat losses. There are two possibilities to achieve significant increases in energy use: Firstly, direct electricity generation (without the detour via heat), for example with wind, sun and water (>> more); secondly, the use of waste heat - such a system is called Combined heat and power.

The two most important ways to efficiently generate electricity: Direct electricity generation with solar, wind and water power avoids heat losses in thermal power plants (above), Combined heat and power uses the resulting waste heat. Own illustration based on a template by the >> WBGU, Sustainable Bioenergy.

Since a heat transport network is required for this, this is only worthwhile if the power plants are not too far away from the heat consumers. Consequence: Large, central power plants should be replaced by smaller power plants with a high degree of efficiency, in which the resulting waste heat as Local or district heating is used for house heating or for commercial purposes. This avoids the generation of carbon dioxide by boilers. By the way, you can use local and district heating also cool in summer - the absorption technology used is the same as that used for cooling with natural gas. So far, combined heat and power has only been used in around 10 percent of electricity generation in Germany. Thought through to the end, part of the electricity generation can also be completely relocated to the heat consumers:

The "energy internet"

Instead of purchasing electricity exclusively from energy suppliers, as was the case in the past, households and other heat consumers such as industrial companies could generate electricity themselves in the future. The basis is heating systems that are equipped with gasoline engines, gas turbines or, most recently, with Stirling engines and generate electricity and heat at the same time (so-called combined heat and power units) - 80,000 units of the natural gas-powered WhisperGen model are to be installed in Great Britain over the next few years. The advantage over larger thermal power stations: The costs of the infrastructure for heat distribution and the resulting losses are eliminated. And: In the future, natural gas could be replaced as an energy source with the help of microelectrolysis systems for the production of hydrogen (>> here). Depending on the entrepreneurial spirit of the user, these systems can be operated by the user himself (which should save him money: industrial companies are already receiving better offers from electricity producers as soon as they even plan combined heat and power systems), or they can be operated as a service by the previous energy supplier, which thereby opening up new business areas.

In the future, such small systems can also be controlled directly by an “intelligent power grid” (>> here) and generate electricity in a targeted manner when it is scarce and expensive, which makes its operation even more profitable.

The necessary conversion of our power generation: More directly generated electricity and
Heat used by means of combined heat and power increase the efficiency of the
Power generation significantly; directly generated electricity reduces fuel consumption
in thermal power plants and the use of electricity generated
Heat reduces fuel consumption in boilers and heating systems. Own
Illustration after >> WBGU, Sustainable Bioenergy.

The system question: do we need new large power plants?

The construction of new fossil fuel power plants repeatedly provokes violent protests: On the one hand, the residents fear environmental pollution, on the other hand, it is feared that carbon dioxide emissions will be resolved for at least the next 40 years. The electricity companies, on the other hand, point out that new power plants are more efficient (and therefore cleaner) than old ones and that the base load supply for industry cannot be ensured without these power plants - and rely on carbon dioxide storage (>> here) to combat the effects of the climate. However, this technology costs considerable energy and thus further reduces the efficiency of the power plants; In addition, it is only worthwhile for large power plant units - so it goes against the climate-friendly cogeneration of heat and power. Since coal mining also has a significant impact on the environment, there is still a long way to go before the much-advertised “clean coal” is achieved. Do we still need the new power plants to secure our electricity supply? Small power plants with combined heat and power use the energy much more efficiently than new, modern power plants without combined heat and power; and they can also compensate for fluctuations in renewable energy sources. Here the system logic of the energy companies associated with the use of fossil fuels (“the bigger, the better”) stands against the requirements of renewable energies, to which clever solutions from many networked small systems are better suited - mainframe computers against the Internet, so to speak (see also >> here) . Scientists are calling for a maximum of 25 percent of investments worldwide to be made in conventional fossil fuel power plants if the 2-degree climate target (>> here) is to be adhered to (see e.g. >> WBGU 2009). The European association for renewable energies EUROSOLAR therefore also calls for the construction of one million small, gas-powered combined heat and power plants to replace 20 large power plants.

The energy sources used to generate electricity in power plants also play a role in the >> fight against climate change: coal contains around 65 percent more carbon than natural gas with the same energy content; and since gas-fired power plants are also more efficient, coal-fired power plants produce around twice as many greenhouse gases per kilowatt hour of electricity as gas-fired power plants. In favor of coal, in comparison to gas, is the significantly larger and better distributed (and thus more difficult to use for political blackmail) supplies; But besides carbon dioxide, they also speak against them. Environmental problems of coal mining. Natural gas, on the other hand, can increasingly be replaced by biogas and, in the future, synthetically produced methane (which is produced from hydrogen that is generated with excess wind and solar power), which means that the combined heat and power plants are also operated with renewable energies. For the base load supply of a decentralized energy system, these are, however, much more suitable than coal-fired power plants as quickly switchable control energy. But why do the electricity companies, who like to advertise themselves as “green giants” (>> From the burden of becoming green. DIE ZEIT via RWE), resist such a system conversion? Quite simply: The previous centralized system of energy supply secures the electricity companies billions in profits every year, and with a decentralized energy supply, in which the municipal utilities or “citizen power plants” play a stronger role, for example, they will no longer coincide in one hand. However, we should not confuse the economic interests of the electricity companies with the economic and energy-political interests of the country, and it is better not to leave the companies to shape the energy transition (see also >> here).

Use final energy efficiently:

With energy-efficient technologies and devices that are commercially available today, energy consumption can be significantly reduced for all forms of final energy use:

Houses and buildings

An average apartment in Germany consumes around 150 kWh / m² per year for heating (>> here); A value of 100 kWh / m² living space is prescribed for new buildings in Germany and 42 kWh in Switzerland. However, it can be done much better.

Passive houses consume a maximum of 15 kWh per year and m², which corresponds to 1.5 liters of heating oil per m² of living space per year. This is achieved through a very well insulated, tight building envelope, windows with triple glazing and a ventilation system with heat recovery. Instead of the usual central heating, it is usually sufficient to heat the air supplied during the cold season; As a rule, the heat gains from the sun, from electrical appliances and the residents themselves as “heating” are sufficient for nine months. When renovating old buildings, consumption values ​​of less than 30 kWh per year and m² can usually be achieved (“3-liter house”), sometimes the passive house standard. The additional costs of passive houses are quickly amortized, especially in new buildings, thanks to the saved energy costs, and the energetic modernization of old buildings also pays off in most cases. In combination with solar energy, such houses can even become energy producers. Examples are the plus energy house by the architect Rolf Disch (>> www.plusenergiehaus.de) or the winning house of the Solar Decathlon 2007 from TU Darmstadt (>> here). Modern approaches and technologies can significantly reduce energy consumption, especially in the large cities of the future (>> more).

In houses whose energy efficiency can be significantly improved through thermal insulation, but heating cannot be entirely dispensed with, there is also waste heat from electricity generation (see above), especially when using directly generated electricity Heat pump considered as a heat source. In the case of electricity from thermal power plants, this is hardly worthwhile from the point of view of efficient energy use (it only compensates for the losses that were previously incurred in the power plant); but if the electricity is generated directly, 0.3 kWh of electricity can deliver up to 1 kWh of heat; Since heat can also be stored well, these heat pumps can also support load management with a power supply from renewable energy sources.

(Only!) With directly generated electricity from solar, wind and water power
Electricity driven heat pumps contribute to energy efficiency and decrease
the consumption of fossil fuels. Own illustration according to
>> WBGU, Sustainable Bioenergy ..

Websites on the subject

>> Website of the Passive House Interest Group www.ig-passivhaus.de
>> Website “Existing low-energy house” of the German Energy Agency
>> Itself is the radiator and
>> Houses like thermos flasks. Two ZEIT articles about passive houses.

>> Green Building Council: US organization that advocates sustainable and energy-saving buildings and that awards a label for particularly ecological buildings (>> Leed = Leadership in Energy and Environmental Design)

Electrical appliances

The best devices on the market often have a consumption advantage of 30 to 50 percent compared to the average stock, and usually save their extra price again through lower energy bills (further information >> here). The LED lamps, which have largely replaced energy-saving lamps and consume less than 20 percent of the electricity of an incandescent lamp, are now a prime example of modern technology. At workplaces, this power consumption can also be halved with modern fluorescent lamps with electronic ballasts and mirrored reflectors.

Stand-by mode is an important waste of electricity; it accounts for a considerable proportion of the total electricity consumption in households. Sometimes it increases the convenience, but often the manufacturers have only saved a few cents for a real power switch. (Self-help is easily possible: Use switchable socket strips for hi-fi systems and computers / screens, for example.) Entertainment electronics have an increasing share of power consumption, with large individual differences: plasma televisions consume two to three times as much electricity as conventional tube sets or LCD televisions. TV. In terms of household electricity consumption, the savings potential by 2020 is estimated to be 25 percent.

What are energy services actually?

Energy services are the real benefits that customers get from their energy consumption: for example, a warm living room or a lighted desk. They are the real need - we don't want to consume energy, we want a warm living room. The energy service is always provided by two components: the (final) energy and an energy converter, in the case of a warm living room, for example, the heating system. With a better energy converter, i.e. a more efficient heating system for a warm living room, the same service can be obtained with lower energy consumption. Therefore, less energy consumption does not mean less energy service. This, and not the energy consumption as such, contributes to our well-being or the efficiency of our economy.

The formula E = EDL x e (Energy consumption = energy service times specific energy consumption) shows what energy efficiency is all about: with the same service, the specific energy consumption (the energy consumption of the converter, in the example above the heating system) and thus the result of reducing the energy consumption. A passive house, for example, reaches the same room temperature as an average house (i.e. the same energy service) with less than a tenth of the energy (see above) - its specific energy consumption is lower by this factor. By the way, the consumer can also cheat higher energy prices: If he wastes cheap energy in a poorly insulated house, it can be more expensive than using expensive energy in a well insulated house: The decisive factor is not the energy price, but the price of the energy Energy service.

Commerce, trade and services

The possibilities for efficient energy use essentially correspond to private households: Office buildings, shops and commercial buildings can also be built according to the principles of passive houses and equipped with energy-saving devices and lighting. There are already examples: For example, the main building of the ETH Zurich's water research institute, which was moved into in 2006, was designed as a zero-energy building without technical heating and cooling (>> more); the energon is in Ulm (>> more). The potential savings in heat generation and hot water roughly correspond to those of households (10 percent by 2020, 15 percent by 2030): Although commercial buildings are not as uniform as residential buildings and are therefore more difficult to record, on the other hand they are renovated or renewed more frequently. The potential for savings in electricity consumption is estimated to be lower, however, since the technical equipment of the workplaces, including information and communication technology, is likely to increase in the future: savings potential of 12 percent by 2020.

Website on the subject

To the savings opportunities in trade >> Corporate energy management.


In the past, some impressive increases in energy productivity (sales per energy input) have already been achieved in industry - usually driven by rising prices. In many companies, however, significant increases are still possible (>> operational energy management), for example through optimized use of compressed air and modern lighting. In terms of electricity consumption, the economic savings potential by 2020 is estimated to be a good 10 percent; this includes a structural change (such as an increase in electric steel production); In terms of fuel consumption, the economic savings potential is estimated at 6.6 percent. In some energy-intensive areas, however, the scope for pure efficiency improvements is exhausted; fundamental improvements can only be achieved here through new processes, for example by replacing energy-intensive chemical syntheses (with high temperatures or pressure) with biotechnological processes that take place at lower temperatures. There are also close interactions with material efficiency in industrial energy consumption (>> more) - less material consumption also means less energy consumption for its production.


Most of the energy in traffic is also lost unused: in a typical car with a combustion engine, for example, just 20 percent of the energy contained in the fuel is converted into drive energy. The rest becomes heat that supplies the heater; however, most of it is lost unused. With electric motors, on the other hand, up to 80 percent of the energy can be used as drive energy; only a part of which is consumed again by the heavier batteries that are used to store electricity. The overall efficiency of the system, however, depends largely on the efficiency of the electricity generation: The 80 percent only applies to the case of direct electricity generation (see above); With electricity from thermal power plants, the efficiency of the overall system is only around 30 percent - still better than with an internal combustion engine, but much worse than with direct electricity generation. Vehicles with batteries also complement a system of direct power generation in that the batteries can act as energy storage devices to compensate for fluctuations in power generation: If there is a lot of energy from wind and sun available, the batteries are charged; if the sun does not shine and if there is no wind, the batteries can have peak consumption cover. More about energy consumption in traffic >> here.

Electric instead of internal combustion engines

The energy efficiency of electric cars is essential when generating electricity directly
better than that of vehicles with internal combustion engines. Own illustration according to
>> WBGU, Sustainable Bioenergy. See also >> here.

The short and medium-term development of consumption in traffic is difficult to estimate; it depends on the one hand on the average consumption of the future vehicle fleet and on the other hand on the development of mileage. Assuming that economical cars will sell better in the future, fleet consumption could drop from 7.7 liters / 100 km (2006) to 5.24 liters / 100 km by 2020 (Greenpeace maintains a fleet consumption of 3 liters / 100 km by 2020 km for possible). With the same annual mileage, consumption would decrease by around 30 percent by 2020. In the case of freight transport, it is to be feared that efficiency gains will be eaten up by increasing traffic.

What does the efficiency strategy bring?

The potential for final energy savings in Germany by 2020 is briefly indicated above (the information is essentially based on a study that the engineering office EUtech carried out for Greenpeace in 2007, see web tips below). Overall, according to this study, the demand for electricity can be reduced by 15 percent by 2020, that for fuel by 11 percent, and the fuel demand in traffic (of which cars make up about half) by 15 percent.

Converted to citizens and day (>> more) this means on the basis of the values ​​from 2006:

Total final energy consumption: 84.9 kWh / day per inhabitant (>> here), of which
- Electricity 22.2 percent (>> here) = 18.8 kWh / day - 15 percent = 16 kWh / day
- Fuels 45.6 percent = 38.7 kWh / day - 11 percent = 34.4 kWh / day
(District heating also contributed 3.1 percent = 2.6 kWh / day to the heat supply)
- Fuel 29.1 percent = 24.7 kWh / day - 15 percent = 21 kWh / day.

In the case of electricity generation, the conversion losses can be reduced by expanding the combined heat and power generation. According to the study, this can be achieved by 2020 5.7 kWh / day contribute to electricity generation. The study also assumes that in 2020 4.7 kWh / day Electricity can be generated directly from renewable energy sources (without conversion losses, see above). This results in the following picture for electricity generation: Electricity demand 16 kWh / day, from that

  • directly generated electricity from renewable energy sources: 4.7 kWh / day (= Primary energy demand)
  • Electricity from combined heat and power: 5.7 kWh / day (With an efficiency of 80 percent, this corresponds to a primary energy requirement of 7.1 kWh / day; the resulting waste heat replaces fuels)

  • Conventionally generated electricity in large power plants: 5.6 kWh / day (With a slightly better efficiency of 44 percent in the future, this corresponds to a primary energy requirement of 12.7 kWh / day)

In order to cover the electricity demand of 16 kWh / day, a total of 24.8 kWh / day of primary energy is consumed, the conversion loss is 8.8 kWh / day. So far, the value for large power plants has been 28.3 kWh / day, so it will be reduced by 19.5 kWh / day. If we assume that the total primary energy consumption (excluding large power plants) and the final energy consumption will decrease, we arrive at a primary energy consumption per inhabitant of 104.2 kWh / day - a reduction of almost a quarter.

Naturally, a look into the future becomes less precise: When, for example, will plug-in hybrid and electric cars catch on and replace fuel with electricity? But the potential for savings is certainly not exhausted (as the electric car shows, see above). At the same time, the potential of renewable energies for electricity generation for the year 2050 is estimated at 15.8 kWh / day and inhabitant (>> here), so that electricity generation from exclusively renewable energy sources appears to be possible even in a highly developed industrial country with electric cars (some scenarios for the world as a whole, see >> here).

The cost of the efficiency strategy

Many of these techniques save up Already money today: like an energy-saving lamp, efficient devices may be more expensive to buy, but they save more than the additional costs through lower energy costs. Even if only efficiency technologies that save money are taken into account, according to Claude Mandil, head of the International Energy Agency (IEA), electricity consumption in the OECD could fall by a third. In Germany, according to a joint study by the Wuppertal Institute and E.ON, 120 million tons of carbon dioxide could be avoided through such measures. Again: by means of measures that are already economically viable, i.e. those that save more money than they cost! The most economical measures include efficient lighting systems, better thermal insulation in commercial buildings, efficient electric motors, energy-saving devices and the thermal insulation of residential buildings.

Further measures are worthwhile if the costs of energy generation are actually taken fully into account: If, for example, the generation of fossil coal electricity is subject to a carbon dioxide levy or tax (>> more), this becomes more expensive - and less competitive with efficiency technologies. However, the total costs decrease because the slowed release of carbon dioxide would cost even more money (>> more). With such framework conditions, energy efficiency could presumably be more than doubled with economic measures. Unfortunately, this does not automatically mean halving energy consumption - more on this in the following box.

Better energy efficiency is not just energy saving

All experience shows that an improvement in energy efficiency does not automatically correspond to the same amount of energy savings. In energy research, this phenomenon is known as the “rebound effect”: the money saved is spent on activities that consume energy, or the progress is partially undone by another use. For example, car engines have become more efficient in the last few decades, but cars have also become heavier and faster - so that the improvements did not primarily benefit gasoline consumption. Something similar could also be observed with the heating. After the renovation of the Schöpfwerk settlement in Vienna, various measures reduced the heating requirement by 77 percent; In practice, however, there were only savings of a good 30 percent - the rest went into higher living comfort. The tenants now heated and used the corridors, which were too drafty before the renovation.

This “rebound effect” means that an energy efficiency strategy alone does not automatically reduce energy consumption, but only in conjunction with clear targets. Energy efficiency is just a means, not the goal. It's good for a heated toilet seat to be energy efficient - but the question still remains of whether a toilet seat needs to be heated at all.

More efficient power generation, more efficient energy use and the replacement of fossil fuels
through direct electricity generation with solar, wind and water power let the carbon dioxide
With consistent use, emissions are reduced by 80 to 90 percent
. That is an order of magnitude
which we also need to prevent catastrophic global warming (>> here).
Own illustration according to >> WBGU, Sustainable Bioenergy ..

Fossil fuels are finite and pollute the environment, atomic energy creates radioactive waste, renewable energies are not available in unlimited quantities, since their technical use requires material expenditure and changes the landscape: Every energy generation has an ecological price. Energy use also has ecological consequences; and also social consequences - for example, mobility can bring people together, but also separate them. Why should an environmental and social price be paid when what we do with the energy is not worth the price? This discussion is not only topical in connection with climate change (if the temperature rise is to be limited to two degrees Celsius or less [>> more], an efficiency strategy is not enough to reduce humanity's carbon dioxide emissions together with the use of renewable energy sources to reduce [>> more]), but also as a fundamental question of whether there can be too much energy consumption? As early as 1985, the Brazilian physicist José Goldemberg asked whether there was a connection between energy consumption and quality of life. Result: The quality of life increases up to around 1,300 watts per person, above this threshold no increase can be determined. (For comparison: the current average energy consumption on earth is 2,500 watts; that of an average German is 5,500 watts.) As a cross-check, Goldemberg also calculated how much energy is needed with modern technology for lighting, cooking, refrigerator, television and traveling, he came to 1,049 watts per person.

This discussion is still largely a taboo. It is also best avoided by many environmentalists, because self-limitation sounds too much like "renunciation" to them. Others, such as Paul Hawken, point out that the limits of nature need not be more restrictive for us than a blank canvas for Paul Cézanne - we can still create incomparable works. In any case, the path to happiness leads through quality instead of quantity (>> more). Every now and then you can find such approaches: Many good cooks, for example, prefer regional ingredients that are appropriate to the season. They do this because such ingredients taste better, but they also avoid energy consumption for greenhouses and transport to distant lands. There is also a fresh start in science and politics: In Switzerland, the Swiss Federal Institute of Technology (ETH) in Zurich has already announced the goal of a 2,000 watt society for the year 2050 (>> more); the city of Zurich committed itself to this goal in November 2008. The discussion will also come up in Germany: How much energy do we really need for a good life? Depending on the requirements, the answer should be somewhere between Goldberg's 1,300 watts for warm countries and the Swiss 2,000 watts for cold countries with heating needs; This is also based on the old question of “human proportions”: Aren't more than a million traffic fatalities a year proof that human limits have long been exceeded at today's speeds; would a “less” result be more? The cheap energy has also led to excesses that have not always made life better; when these excesses are ended, there is also an opportunity.

The ecological importance of decreasing energy consumption

In the reference scenario of the >> World Energy Report 2008 of the International Energy Agency, global energy consumption will increase by around 45 percent from 2006 to 2030; the emissions of the greenhouse gas carbon dioxide from 28 billion tons to 41 billion tons per year. Renewable energy sources could not fundamentally change this either: In 1995 the oil company Shell published a “World Energy Scenario” in which 60 percent of the energy requirement was covered by renewable energy sources in 2060 - carbon dioxide emissions would still double. With unrestrained energy demand, the consumption of fossil fuels would have to increase further; no alternative energy source could prevent this.

Given the multitude of economically viable, efficient technologies for using energy, the attempt would also be nonsense - it has often been compared to pouring more water into a holey bucket instead of sealing the bucket first. Then, in connection with efficient use of energy, the picture looks completely different. For example, the potential of efficient energy use has been calculated for the study >> Energy (R) Evolution by Greenpeace: Despite growth in world population and economy, energy consumption in 2050 could be lower than it is today. The result has now been confirmed by other studies.

The consistent reduction in energy consumption on the one hand reduces the environmental pollution associated with energy production, on the other hand it offers the opportunity to actually replace fossil fuels with >> renewable energies: Only this would really reduce air pollution and the climate change caused by energy production. A real turnaround in the emission of the greenhouse gas carbon dioxide will only be achieved within the network (according to the studies mentioned above, a reduction of 50 percent is then possible); Only in the network can the further advantages of a different energy policy be achieved: less geopolitical dependence on insecure oil and gas supplier countries, preparation for the (rather) short or long time running out of oil and gas supplies, less vulnerability a more decentralized energy supply against possible attacks by terrorists, and less dependence on a few electricity producers who can dictate prices. (The role >> renewable energies are presented on the next page.)

Web tips

>> Energiewende - The website of the Öko-Institut (which created the basis for the topic in 1980 with the book “Energiewende” in Germany)

>> Energy transition towards sustainability - the study by the German Federal Government's Scientific Advisory Board from 2003, with the option of downloading as a pdf

>> Climate protection: Plan B The national energy concept from Greenpeace: How Germany can reduce its carbon dioxide emissions to almost zero by 2050 without nuclear power, with the possibility of downloading the study as a pdf

>> Energy topic - A website from the German Energy Agency (dena) with tips on how to save energy and information on renovations and financing, but also on the topic of energy generation

>> Energy efficiency initiative - also a dena website >> Energy advice from consumer centers

Continue with:
>> Renewable energies instead of fossil fuels
>> A possible energy future

On the subject see also:
>> World Energy Report 2008: The International Energy Agency's outlook up to 2030

Back to:
>> Strategies for the future overview page

© Jürgen Paeger 2006 - 2009

Energy and jobs: Measures for energy efficiency and the expansion of renewable energies create jobs, at the same time there are no jobs in the fossil energy industry. And since renewable energies are even more expensive than fossil fuels, consumer demand is reduced and more jobs are lost. But all studies show: net, that is, taking job losses elsewhere into account, energy efficiency and renewable energies create jobs; in Germany alone there are hundreds of thousands.

Local heating is basically the same as district heating, only the heat is transported over shorter distances. Often no distinction is made and people generally talk about district heating.

The green electricity provider Lichtblick offers such a concept in Hamburg (and from 2010 nationwide) under the name Swarm of energy (>> more). The company SenerTec (the “Dachs”, >> more) sells small combined heat and power plants.

Homeowner? Information on thermal insulation, heating modernization and funding opportunities can be found >> here

Kilowatt hours? For the units of power and energy and their conversion see >> Energy and its units.

If all apartments in Germany had at most the energy consumption of passive houses, the energy requirement for heating would be included 1.6 kWh / day. Since only around 2 percent of the housing stock is renovated every year, consumption is falling rather slowly. A reduction of 10 percent by 2020 and 15 percent by 2030 seems realistic.

With modern devices, the consumption of electrical devices can be cut in half.

Anyone who wants to save even more money can in future have their electrical devices controlled by an “intelligent power grid”, >> here

The lighting of the future: Electric light during the day - there will be less and less in the future. With clever mirror systems, daylight can be directed deep into the interior of the building. This not only saves electricity, but also reduces the need for cooling in summer. Entire institutes in the USA are already researching this topic - search for "Daylighting Lab" with your search engine.

For the current energy consumption in traffic, see >> here.

The deliberate limitation of energy consumption will Sufficiency strategy called; it goes against the notion that more is always better.