Which countries are operated with 100 renewable energies?

This is how climate protection works: 100% renewable energies by 2040 at the latest

German politicians like to describe Germany as a pioneer in climate protection. Most of our energy supply is still covered by climate-damaging fossil fuels. By the year 2040, however, our energy supply could be completely converted to carbon dioxide-free renewable energies, as the excerpt from the book Renewable Energies and Climate Protection shows.

The climate can only really be saved if all countries in the world reduce their greenhouse gas emissions to almost zero as quickly as possible. But many cannot even imagine a life beyond oil, natural gas or coal.

It was not even 300 years ago when regenerative energies completely covered the earth's energy supply. In a good 200 years, the global energy supply will almost certainly be completely free of carbon dioxide again. Because by then, at the latest, the last deposits of fossil fuels will be exhausted. As a result of the roughly 500-year history of the use of fossil fuels, the climate would collapse completely by then. If we want to largely save the climate, we must achieve a carbon dioxide-free energy supply much earlier. We still have around 30 years to do this.

Development of the shares of different energy sources in the world primary energy demand and two future development possibilities

However, a climate protection scenario for Germany should first show what a quick path for the energy transition towards a sustainable and carbon dioxide-free energy supply could look like and what role regenerative energies play in this. The responsibility that rests on Germany is enormous. Many other industrialized countries are looking spellbound to Germany and whether it will be possible to implement the full-bodied energy transition without any problems. If we succeed in doing this, it will automatically spread to the rest of the world.

Compared to other countries, the possibilities for using renewable energies in Germany are anything but optimal. But if it is possible to supply a densely populated industrial country like Germany with only moderate regenerative energy potentials completely with renewable energies, this should certainly not pose a problem for other countries. Germany's leading role also offers numerous advantages in the long term. For Germany, this role is already paying off. Renewable energy technologies are developing into export hits for German industry.

However, the climate protection scenario outlined here is not a sure-fire success. Especially the profiteers and supporters of the traditional energy industry are trying to delay the change in energy supply. Cost arguments are intended to prove that rapid restructuring is unacceptable for the German economy and the population. The transformation to a sustainable energy supply is of course associated with considerable investments. In the long term, however, a carbon dioxide-free energy supply can save considerable costs, which would have to be spent on combating the consequences of climate change and constantly increasing costs for fossil fuels. Due to the resistance, the change is unfortunately not yet taking place at the necessary pace. With a slight increase in the rate of conversion, however, a carbon dioxide-free energy supply in Germany could be achieved by 2040, as the following climate protection scenario shows.

Down with the primary energy requirement

The development of the total primary energy demand in Germany gives an overview of the necessary changes. This includes original forms of energy such as coal, crude oil, natural gas, uranium but also regenerative energies. Hydrogen is also listed here as a primary energy carrier, analogous to electricity from regenerative power plants, although this must first be produced using regenerative electricity. In 1990, fossil fuels and nuclear energy together accounted for almost 99 percent of primary energy consumption. This year, renewable energies only contributed a good one percent to covering the energy demand. By 2012, the share of renewable energies had already increased to 12 percent. However, there is still a long way to go before a one hundred percent regenerative energy supply is achieved.

Between 1990 and 2010, nuclear energy had a share between 10 and 14 percent. In 2012 this had already fallen to 8 percent. As a result of the exit decisions, a continuous decline in the share of nuclear energy and, ultimately, an end to the use of nuclear energy in Germany by 2022 can be expected. However, this exit path is not ambitious. It is entirely possible to end the use of nuclear energy in Germany a few years beforehand.

While the total primary energy demand fell only slightly between 1990 and 2012, it will decrease significantly by 2050 as a result of more efficient energy use and falling population numbers. Since the power plant efficiency is not included in the calculation of the primary energy consumption of electricity from wind power, hydropower or photovoltaic systems, in contrast to coal and nuclear power plants, the primary energy requirement also decreases due to statistical effects. Overall, the primary energy requirement in Germany can be more than halved.

Possible development of the shares of renewable energies in total primary energy consumption in Germany

However, the restructuring of the energy industry in Germany will be around 10 to 15 years too late for effective climate protection as early as 2020. Instead of the recommended greenhouse gas reductions of 50 percent, 30 percent is more realistic. An extension of the operating times for nuclear power plants would not have helped to achieve the goals for 2020 either. An extension of the term hinders the rapid restructuring of the energy industry without making the necessary contribution to climate protection. The climate protection goals for the years 2040 or 2050 can, however, be achieved without any problems if the path towards them is consistently pursued.

The energy mix in 2040 must be based on a broad regenerative portfolio. Due to the geographic location, the potential of hydropower is the lowest. In addition to domestic regenerative energies, the import of inexpensive solar and wind power from sunny and windy regions can contribute to a secure and cost-effective energy supply to a lesser extent.

Electricity generation entirely without nuclear and fossil power plants

While a major decline is to be expected in the total primary energy demand in Germany over the next few decades, electricity consumption will probably continue to rise. There is also great potential for savings when it comes to electricity. However, the trend towards more and more new electrical appliances and the increased use of heat pumps and electric cars will more than compensate for this.

The conversion to a regenerative energy supply has already begun in the electricity industry. In 1990 only hydropower had a noteworthy share of the electricity supply with around 3 percent. In the following 20 years, wind power, biomass use and, most recently, photovoltaics were added. Their combined share was already around 23 percent in 2012. By 2020, renewable energies can already cover around half of the demand and by 2040 secure the entire electricity supply.

Possible development of the share of renewable energies in gross electricity consumption in Germany

For this, however, we need a completely different supply structure than in the past. Fluctuating regenerative power plants will take over the largest share. While it is practically impossible to develop new potential in hydropower in Germany, wind power and photovoltaics have the greatest potential for expansion. In theory, both wind power and photovoltaics could each alone cover the entire electricity demand in Germany. In practice, however, this makes little sense because the supply of wind energy and solar radiation, which fluctuates over the year, would require storage systems that are too large and expensive. With a sensible combination of different renewable energies, the storage requirement is reduced considerably. Because of their great potential, photovoltaics and wind power will together generate more than two thirds of the annual demand in the future.

Fossil power plants and nuclear power plants are no longer necessary for a safe and climate-friendly electricity supply by 2040 at the latest and will become a hindrance even beforehand. With the exception of gas-fired power plants, they cannot function as a bridge, as is often claimed. Lignite and nuclear power plants in particular are difficult to control and hinder intelligent operation in networks with high fluctuations in supply. Gas-fired power plants, on the other hand, can be regulated much faster. The fossil, climate-damaging natural gas can finally be gradually replaced by biogas and regeneratively produced hydrogen or methane.

Insulation and renewable energies for heat supply

In contrast to the electricity sector, considerable reductions in energy requirements can be achieved in the case of heat supply. The savings opportunities in the building sector make it very likely that the heating requirement will be halved by 2050 compared to 1990. It is important that politicians strongly promote modernization measures in existing buildings.

Possible development of the share of renewable energies in the primary energy demand of the heating sector in Germany

In 2012, the share of renewable energies in the heat supply was a good 10 percent. Among the renewable energies, biomass - i.e. firewood - made up by far the largest share. However, the possibilities for using biomass in Germany are limited. For this reason, various regenerative energies will also ensure the supply of heat.

In addition to solar thermal energy, geothermal energy and heat pumps can also make greater contributions. In the longer term, the remaining demand could be covered by regeneratively generated hydrogen. If the direct electricity demand and the district heating come from renewable electricity power plants as described above, a carbon dioxide-free heat supply would also be possible in Germany in 2040 with some efforts.
Increased efficiency and new concepts for transport

From today's perspective, the climate-friendly redesign of the transport sector seems to be the greatest challenge. In the recent past, German automobile manufacturers have repeatedly shown great directional stability in their resistance to the implementation of climate protection measures. Senior managers even claimed that the savings required were simply physically impossible. Today's cars are by no means energy-saving marvels. Even modern internal combustion engines only achieve an average efficiency of around 25 percent in the ideal case. At least 75 percent of the energy content dissipates as waste heat unused into the environment. If you ignore all the emotions with which the topic of cars is obviously connected in Germany, it would appear technically possible to halve the energy requirement.

With new innovative drive concepts such as electric cars or fuel cell vehicles, the efficiency can be increased, the energy requirement reduced and ultimately the carbon dioxide requirement reduced to zero with regenerative energies.

Possible development of the share of renewable energies in the primary energy demand of the transport sector in Germany

For conventional vehicles with internal combustion engines, biomass fuels can cover part of the fuel requirement in the short term. However, the agricultural land in Germany is not even close to being able to cover the overall demand with biomass fuels. In addition, part of the available biomass is required to generate electricity and heat.

Thanks to significant improvements in battery technology in recent years, electric cars will soon be ready for series production. In the transition period, they would still be partially charged and powered by electricity from fossil fuel power plants. However, as the share of renewable energies in the power supply increases, carbon dioxide emissions then decrease quickly.

From today's perspective, fuel cell cars fueled with regenerative hydrogen will come onto the market later. There are already considerable advances in the development of fuel cell technology. However, there are still no structures for the carbon dioxide-free production and distribution of inexpensive hydrogen. In the long term, however, hydrogen technology can make a contribution to climate protection. This could then also cover the energy needs of the transport sector without carbon dioxide by the year 2040.

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