F or the technical prophet and novelist Jules Verne, the energy problem of our civilization was never an issue. As early as 1875, in his work 'The Mysterious Island', he let it be known: 'Hydrogen and oxygen, either alone or together, will become an inexhaustible source of heat and light, of an intensity that coal could not have at all; water is the coal of the future.
This brave forecast comes in handy for the German Hydrogen Association (DWV) in 2012, which is why it also precedes its presentations published on the Internet as a guiding principle. At the same time, parliamentary groups show a pink future for hydrogen: around half of all required energy could be drawn from reactions of the element hydrogen in 2050. A vein of hydrogen gas pipelines will then run through Germany, networked with old natural gas storage facilities that have been converted into hydrogen storage facilities Solar panels on the roofs of the houses continuously produce electricity, the surplus of which is used for the electrochemical splitting of water (hydrolysis ) to be used. If the solar panels do not work due to a lack of solar energy, the stored hydrogen could be converted into electricity again in a fuel cell installed in the cellar. This system of chemical electricity storage also works on a large scale with pumped storage power plants and maritime wind farms.
Only 30 hydrogen filling stations in Germany
However, there are still a few problems with the necessary infrastructure in the way of this pretty idea in the Vernesche sense, not to mention the case in which hydrogen is to be used. Until last year, for example, there were only around 30 hydrogen filling stations in Germany, seven of which were integrated into a public network. In 2015, when Daimler wants to offer and deliver the fuel cell technology in small series, there should be 20 more: Daimler and partner Linde go into the submission for the construction of the stations, which can cost up to 1.5 million euros each. Even 180 hydrogen filling stations on German autobahns would only cover around two thirds of the entire autobahn network; around 1,000 dispensing systems would be necessary for a nationwide supply. But who is supposed to raise the necessary estimated 1.5 billion euros in construction costs is still in the stars.
Other problems are caused by the bad oneEnergy balance of hydrogen. DWV: 'You first have to get the hydrogen into the connection for storage and get it out again for consumption in the vehicle. Both are associated with losses.' The energy required to generate hydrogen from renewable biomass, for example, combined with the storage and conversion losses, ensure that the efficiency of the alternative fuel in the vehicle is around 30 percent. In addition to the poor overall efficiency, which places hydrogen behind the modern
combustion units in the CO2 balance, the handling of the element when used in vehicles has not been sufficiently clarified. 'So far there is no process for the chemical storage and release of hydrogen in vehicles,' the DWV announced on July 4, 2011, 'that is mature and tested enough for use in series models. Most of them are in the laboratory stage and could at the earliest be ready for use in ten, more likely 15 years. '
The association's forecast for the future sounds more like a wish for human ingenuity than a concrete plan for an infrastructure program that can be implemented quickly:' Nobody can rule out that In the medium or long term, an attractive chemical storage process emerges, even if none is in sight at the moment. '
The only thing missing is gas propulsion on the will of the buyer
Our colleagues from gas incineration are already one step further. Gas made from wood or coal and water vapor has been used for lighting and heating for more than 200 years, and gas engines were also the forerunners of the gasoline-powered four-stroke engine. Pipeline networks and tanks are available worldwide - the only thing missing is the willingness of buyers to buy gas-powered cars. In the USA there are only about 130,000 gas customers for a total of around 140 million vehicles; In Germany, of around 42 million passenger cars, only 75,000 have been filled with GNG so far. Gas-powered automobiles are not suitable for environmental zones in which the zero emission limit applies. Car engines powered by natural gas or liquefied gas produce around 20 percent less carbon dioxide than their petrol-processing counterparts, but with the comparatively emission-free energy sources hydrogen or electricity, neither compressed natural gas (CNG) nor liquefied petroleum gas (LPG) can keep up.
Im Compared to building a hydrogen infrastructure, the problems associated with charging electric cars look downright cute at first glance. The previous field tests on e-mobility have finally shown that charging is predominantly carried out at home or at work. Who needs public charging stations? All you need is a free socket and you're ready to go. In the worst case, a cable has to be laid in the garage - one of the easiest exercises for any electrician. Butthat's only part of the truth. Many electricity drivers are plagued by the fear of getting stuck on the road, which is why they only make limited use of the range of their battery companions. A study from Tokyo shows what happens when public charging stations are suddenly added: They are actually only rarely used, but the confidence of drivers in their Stromer increases considerably, and with it the distances covered. After all, tapping a few kilowatt hours in an emergency sounds more tempting than having yourself towed away. The establishment of a public emergency supply is therefore indispensable as a confidence-building measure in the new technology.
Electromobility is also a new business field
No wonder that most power producers have long seen electromobility as an additional business area. RWE already has 1,600 charging stations across Europe. There are also fast charging stations at motorway filling stations with an output of up to 50 kW. A range of 100 kilometers can theoretically be recharged in less than 30 minutes. Nine pillars on the A1 between Cologne and Hamburg serve as emergency nails and already enable cross-country journeys with a radius of over 400 kilometers. The Stromer will remain unsuitable for frequent long-distance excursions for the foreseeable future, as only travelers with the serenity of Buddhist monks want to take a half-hour break every 100 kilometers. But here too the acceptance of the Watts men is likely to increase in line with the knowledge of the possibility in exceptional cases. The compact Stromer Renault Zoe, which will be available from autumn, is already designed for fast charging stations up to 22 kW and the Smart Fortwo ED is also available in a corresponding version Has a garage with electricity available? Freely accessible charging cables, which are used to fill the batteries overnight, cause discomfort not only for reasons of cost. Even vandals and pranksters could give the copper lines to stupid ideas. Audi is therefore developing a system for contactless, i.e. inductive, charging. A principle that everyone who has used an electric toothbrush is familiar with. If a suitably equipped electric car comes to a stop above a charging plate in the floor, the charging process starts when the alternating current in the floor plate induces a magnetic field in a coil in the car. There the current is rectified via a converter and charges the battery. Laying such loading plates is not only conceivable in residential streets where cars are parked overnight. Even at red lights, it can be used to recharge a few watt hours - and this is also gentle. The short charging strokes put less stress on the juice dispenser than completely filling up a completely empty battery.
E-cars are not clean without clean electricity
How the electricity gets into the electric car is clear so far. However, there are more problems at the other end of the cable: According to the German Energy Agency, the need for additional power transmission networks will be 3,600 kilometers by 2020. By then, 40 to 50 percent of German electricity should come from renewable sources - mostly from wind farms in the North Sea Only with a high proportion of regenerative energy does an electric car drive cleaner than a current combustion engine. However, the electricity from the structurally weak north still has to be sent to the metropolitan areas of the Ruhr area and southern Germany. And that is exactly where the problem is up to 15 years, also because the acceptance of new masts in the population is very low. Since the expansion of renewable energy is progressing faster than expected, it will in a few years more wind power than can be transported.
Even more sobering is the hope for a pan-European power grid that connects wind power plants in Scotland or the Baltic Sea with solar parks in Spain or southern Italy. Compensating for weather-related energy bottlenecks is only possible at distances of several 1,000 kilometers. Then the wind is always blowing somewhere and the sun is always shining somewhere. But the necessary political structures (regulatory authorities) are already lacking to establish such a super network. The interest of the national network operators also remains vague; after all, import capacities always mean competition and thus falling prices.
Electricity storage is the key
So comes the storage of renewable electricity is of immense importance. According to the Federal Ministry of Research, there will be a storage requirement of up to 50 terawatt hours (TWh) by 2050. For comparison: the capacity of today's storage is only 0.04 TWh. Since pump storage such as electricity pylons are extremely unpopular with the population, alternative - such as chemical - storage methods are desperately sought.
It is comforting that the gigantic challenges and problems surrounding the energy transition only affect electric cars to a small extent. If all traffic in Germany were electric, power consumption would only increase by 15 percent. One million Stromers, outlined by the federal government as an ambitious target for 2020, would have a power share of just 0.4 percent.