The silent, low-vibration motor requires few auxiliary units and saves a long shaft tunnel. Exhaust cleaning is usually not necessary thanks to the optimal external combustion. H2 or bio-LNG are suitable as climate-neutral fuels. With a suitable design of the burner, you can also change the fuel from port to port, for example to diesel.
In addition, there is no metane slip: Since methane is around 20 to 25 times more harmful to the climate than CO2, it is more harmful to the climate than diesel as an alternative fuel in conventional ship engines.
Low-vibration, silent and low-emission operation is particularly advantageous on passenger ships.
The solution: A single New Stirling Engine replaces both existing systems, the classic diesel drive and the space-consuming AIP at the same time. You can always ride full power over and under water. You only have to carry enough O2 in the tanks, which is easy to achieve: 0.58kg O2 are required for a stoichiometric combustion of 1kg diesel. 1000l of diesel therefore only require 1.00 m³ O2 at 335 bar.
The decompression of the O2 to ambient pressure creates an immense temperature drop, which can be used to cool and improve the efficiency of the Stirling system while at the same time reducing the heat signature.
The result is a long range, less complexity, noiseless operation with a high level of efficiency, and less space required. Nobody needs nuclear submarines anymore.
The main problems with heat recovery in steelworks are that the supply of waste heat exceeds demand and that electricity generation in turbines only takes place at low levels of efficiency, essentially because a constant heat source would be necessary for optimal operation. Turbines can only use previously extracted heat in the form of steam or gas.
The New Stirling Technology provides a remedy here. The intermediate storage and smoothing of the waste heat can take place in thermal accumulators. The transfer of waste heat to steam or gas is often not required or is very simple. The heat can then be transferred to the New Stirling Technology via circulating air circuits.
Many waste heat leaks in production, for example wall heat, can now be used to generate electricity ("Heat To Power"). In the coking plant, for example, around half of the energy used remains as sensible heat in the hot coke. Further potential heat sources are the converter gas and exhaust gases from the electric arc furnace with scrap preheating, blast furnace slag, converter slag, cast steel and rolling steel. In principle, all warm system surfaces can serve as a heat source.
Just like in steel works, the surface heat can be fed to the Stirling plant with circulating air systems and used to generate electricity.
The consequences of unreliable generation are expensive, unprofitable backup power plants, dependence on gas, necessary grid expansion, curtailment of electricity generation and its payment, export of excess power at negative prices, overcapacity in renewable energy generation, etc. etc.
Renewable energies only make sense if all outputs above the average are smoothed and stored. The stored energy can then be recovered if necessary. This sounds simple, but in practice it is also associated with considerable losses. When using micro turbines, the electrical efficiency can usually only be settled at 25-35%. Whether the remaining energy (waste heat) can be used depends on the local conditions.
The only cost-effective, resource-saving, quickly realizable option for the temporary storage of energy peaks in the required order of magnitude and with manageable effort is the use of high-temperature heat storage systems and the reconversion of the heat stored therein into electricity Energy in a New Stirling Plant.
A New Stirling System in connection with thermal storage will surely exceed the previous efficiency of 40% for H2 or 25 ... 30% for micro turbines by far.
High-temperature heat storage and the New Stirling plant can also be placed decentrally in tandem, e.g. linked to a district, and then used as part of a combined heat and power system.
The German research institute GWI (Gaswärme Institut e.V., Essen - Gas heat institute) has been researching in this direction since 2008 and developing COSTAIR burners for efficient combustion. Now it's time to use this to feed a New Stirling Plant.
Most of this waste heat is currently lost: only a third of the energy supplied to the technical processes is used. The problem with its use is similar to that of regenerative energies: This form of energy occurs cyclically and must be temporarily stored or smoothed out. In addition, the waste heat must first be collected and made available for reconversion, which is often difficult, if not impossible, with the existing systems and also usually unprofitable.
The solution to this task also leads to the same result: high-temperature heat storage systems could absorb the energy and thus continuously drive a New Stirling Plant. Such a constellation would not only be more efficient, but it also opens up completely new possibilities for the use of heat, which occurs in places that were previously never considered. In addition, this application is much simpler in design and opens up new, cheaper installations for tapping and storing heat.
The system proposed here, on the other hand, simplifies the system again. The efficiency of the subsequent New Stirling Plant can be optimized if a high-temperature heat storage systems is preheated with industrial waste heat and any peak temperatures in the storage tank that have not been reached are brought to the final temperature with peak outputs from regenerative electricity generation .
The cement sector is a major greenhouse gas emitter, responsible for around 7% of CO2 emissions worldwide and around 4% in the EU. Burning fossil fuels to meet heating needs accounts for 35% of cement's CO2 emissions. The remaining 65% are due to direct process emissions.
Even a New Stirling System cannot change much about this, but ...
Thermal image photo of the 92m long rotary kiln from Tianrui Group Cement Company, China