Which of the following can help increase energy efficiency in the transportation industry? cogeneration smart meters LEED certification hydrogen fuel cells molten salt systems

The question is asking which of the given options can help increase energy efficiency in the transportation industry. Let's analyze each option:<br /><br />1. Cogeneration: This is a process where waste heat from a power plant is used to heat buildings or industrial processes. While it can increase energy efficiency, it is not specific to the transportation industry.<br />2. Smart meters: These are advanced electricity meters that can record the consumption of electricity in near real-time. They can help consumers and utilities manage energy use more efficiently, but they are not directly related to the transportation industry.<br />3. LEED certification: This is a green building certification program that recognizes buildings that are environmentally responsible. While it promotes energy efficiency in buildings, it is not directly related to the transportation industry.<br />4. Hydrogen fuel cells: These are a type of fuel cell that uses hydrogen as a fuel. They produce electricity without combustion, making them a cleaner and more efficient alternative to traditional internal combustion engines. This is directly related to the transportation industry as it can be used in vehicles.<br />5. Molten salt systems: These are used in concentrated solar power plants to store thermal energy. While they can increase energy efficiency in power generation, they are not specific to the transportation industry.<br /><br />Based on the analysis, the correct answer is "hydrogen fuel cells" as they are directly related to increasing energy efficiency in the transportation industry.