The internal combustion engine has been around for over one hundred years, and there is still significant scope to improve it further. However, new technologies and innovations make it more efficient and environmentally friendly. These innovations are making it easier to create vehicles with less energy. For example, Toyota has released patents for fuel cell and plug-in hybrid technologies and is also working on a fully electric vehicle.
Alternatives to the internal combustion engine
In the past sixty years, the internal combustion engine has been the most popular power source for cars and other vehicles. Its versatility has made it a common choice for many applications. Internal combustion engines power everything from lawnmowers to rockets, but they are perhaps most widely associated with cars. However, recent years have seen increased scrutiny regarding internal combustion engines’ environmental and pollution risks. Therefore, governments, corporations, and environmental groups are now looking for practical alternatives.
A gasoline-electric hybrid is one of the most popular alternatives to the internal combustion engine. The Toyota Prius is a gasoline-electric hybrid that combines a gasoline engine with an electric motor and battery pack. As the car drives, the battery recharges. As a result, the car uses less gasoline.
Alternatives to the internal combustion engine are a growing market and may eventually replace gasoline as an everyday fuel for cars. The cost of gas is falling, and environmental concerns are pushing automakers to develop alternatives. Electric vehicles and fuel cells have the potential to reduce emissions and may even be profitable within a decade or two.
Several alternatives to the internal combustion engine have been introduced over the last several decades. However, not many of these technologies have been proven in production, but many have been in development and have shown promising results. However, while these alternative technologies are an essential step towards making cars more environmentally friendly, there are still a few significant hurdles to overcome before they reach widespread use.
These alternatives are based on the theory that the combustion of air, fuel and exhaust gases is similar. Despite the differences in the composition and combustion characteristics, alternative fuels have varying effects on emissions and engine performance. However, future research could lead to hybrid energy that would reduce emissions while improving engine performance.
Technologies that extend their life
While the internal combustion engine has been around for many decades, there have been some significant advancements in technology that can extend its life. One of these advancements is free valve technology, which uses pneumatic actuators to open and close valves in the engine, replacing the traditional camshafts. This technology has improved fuel economy and decreased greenhouse gas emissions.
Displacement on demand (DOD) shuts off unused cylinders at highway speeds, and variable compression ratio (VCR) lets the engine run more efficiently depending on speed and load. Another technology is high-pressure direct injection, which atomizes fuel into fine particles that help improve combustion and decrease emissions. Micro-hybrids are another emerging technology that uses a small electric motor to help smooth torque and start-stop systems.
The next step in extending the life of the ICE is to increase the engine’s fuel efficiency. With current ICE technologies, fuel efficiency gains of up to 15% are possible. In addition, improved ICEs can reduce CO2 emissions by up to 10%. Further developments are needed in biofuels and exhaust gas after-treatment systems.
Another step forward is the use of sensors in the combustion process. These sensors have enabled more precise control of the air/fuel mixture. Furthermore, the valvetrain plays a vital role in combustion engines, as it has to adapt to the load and maintain the correct air/fuel mixture. As part of this evolution, Tier-one supplier Schaeffler is introducing a new electric cam phasing unit that makes rapid adjustments according to speed. This allows the valve timing to be optimized over the entire operating range.
Although internal combustion is expected to be replaced by electric propulsion shortly, it may also survive as the primary form of propulsion in some niche markets. This includes niche markets like small sports cars. However, specific technological advances could extend the life of the internal combustion engine.
Innovations that reduce its environmental impact
The internal combustion engine (ICE) is a proven technology that powers more than ninety percent of the world’s transportation. Today, 95% of that energy comes from petroleum fuels. Alternative fuels like biofuels have made some progress, but their base is relatively low, and they face several barriers to unlimited growth. In the next few decades, the IC will continue to be the dominant engine on the world’s roads, especially for heavier vehicles. As the market moves to greener fuels, ICEs will need to be improved to reduce their environmental impact.
While the internal combustion engine is not pollution-free, it is less polluting than many animal fuels. Unlike animal fuels, gasoline-powered engines are less polluting than just a few years ago. This means that they will be cleaner in the next few years.
While the current emission control systems efficiently convert NOx emissions during highway driving, further research is needed to address higher NOx emissions in urban driving. Innovations in this area include larger catalyst volumes, continued powertrain hybridization, and advanced after-treatment systems. These innovations are inexpensive, and industry experts estimate they will not significantly increase vehicle costs. Some of these innovations can even improve cold-start emissions in entry-level gasoline vehicles. They can also help light diesel vehicles meet Euro 7 emissions standards.
Increasing fuel efficiency is another way to lower emissions. Innovations that improve fuel efficiency can improve emissions and fuel economy while extending the engine’s life. Furthermore, new technologies can reduce the machine’s noise and vibration, improving the vehicle’s drivability.
Other improvements include co-designing the engine and fuel system. Dual-fuel and single-fuel technologies significantly promise to improve fuel efficiency and reduce emissions. The machines can optimize their intended application by incorporating a wide range of fuels and advanced combustion modes. Furthermore, biofuels and synthetic fuels are being developed to reduce carbon dioxide emissions.
The diesel emissions reduction act of 2010 reauthorized the DERA grants and authorized up to $100 million in funding annually for FY2012 through FY2016. These funds are expected to help manufacturers reduce UHC, particulate matter, and NOx emissions. In addition, these technologies must also maintain the thermal efficiency of the internal combustion engine.
Miniature nuclear reactors
One potential solution is to use a miniature nuclear reactor to power an internal combustion engine. The mPower reactor, developed by Babcock & Wilcox, is a 500 MWt, 180 MWe integral PWR. The reactor is factory-made and rail-mounted. The company’s design is conservative and can run for 5 to 10 years without refueling or servicing.
The most miniature land-based version is 13 m long, 8.5 m in diameter, and has a mass of about 600 t. The most prominent version has a diameter of more than 10 m and a group of about 3000 t. The reactor uses a KLT-40 core with an average burn-up of 95 GWd/t. The typical lifespan is around 40 years.
The VOYAGER reactor has a design approved by the European Union. The reactor is factory-built and features a three-meter-diameter pressure vessel and convection cooling. The reactors use standard PWR fuel enriched to 4.95%. The fuel assemblies are about 2 m long and 4.6 m in diameter. A cylindrical containment vessel module weighs about 640 tonnes.
The modular reactor design lends itself to putting multiple units on the same site. It also has a lower cooling water requirement. This makes it ideal for remote areas or specific applications. In addition, it allows for in-situ decommissioning. The IAEA recently published an updated version of its SMR book, including contributions from developers and 70 new designs.
China’s Nuclear Power Institute has been working on prototypes of these reactors. One of the prototypes, ACP100, is a small modular reactor with passive safety features. It has 57 fuel assemblies and integral steam generators at 320 degrees Celsius. It produces about 125 MWe of power and can supply more than 10,000 m3/day desalination.
Another model is the MRX. Its designers say this design suits local energy supply and marine propulsion. The MRX reactor uses fuel with an enriched level of 4.3%. Its fuel refueling interval is about three years.
