Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
ME 417 Project 1
| Question | Answer |
|---|---|
| what is a hydrogen fuel cell? | device that converts chemical energy from hydrogen and oxygen into electrical energy |
| is a hydrogen fuel cell a heat engine? | no, it is an electrochemical device not a heat engine |
| does a fuel cell burn hydrgoen? | no it uses electrochemical reactions instead of combustion |
| what are the main inputs to a hydrogen fuel cell? | hydrogen fuel and oxygen from air |
| what are the main outputs of a hydrogen fuel cell? | electricity, water, & heat |
| what happens to hydrogen inside the fuel cell? | hydrogen is split into protons and electrons at the anode |
| what happens to the electrons? | they flow through an external circuit creating electrical power |
| what happens to the protons? | they pass through the proton exchange membrane to the cathode |
| what happens at the cathode? | protons, electrons, and oxygen combine to form water |
| what role does the membrane play? | it allows protons to pass through but blocks electrons |
| in what form does useful energy enter a hydrogen fuel cell? | as chemical energy stored in hydrogen |
| in what form does useful energy leave the fuel cell? | as electrical energy |
| why does heat leave the fuel cell? | because not all energy can be converted into electrical work |
| what is the overall energy conversion? | chemical energy --> electrical energy + heat |
| why is heat considered an energy loss? | because it cannot be fully converted into useful work |
| are hydrogen fuel cells 100% efficient? | no |
| why cant fuel cells be 100% efficient? | because irreversibility's generate entropy, requiring energy to be lost as heat |
| what is irreversibility in simple terms? | when some power is lost as heat and cannot be used for work |
| what law of thermodynamics limits fuel cell efficency? | the second law of thermodynamics states that the |
| do fuel cells still follow the second law? | yes, all real systems do |
| why are hydrogen fuel cells expensive? | due to costly catalysts, manufacturing, and maintenece |
| what materials increase fuel cell cost? | precious metal catalysts like platinum |
| why is hydrogen storage difficult? | it must be stored at very high pressures or very low temperatures |
| why is hydrogen storage a safety concern? | high pressures and low temperatures increase risk and system complexity |
| why isn't hydrogen always environmentally clean? | because it must be produced using energy, which may create emissions |
| what is a catalyst? | a substance that speeds up a process without being used up |
| why are catalysts needed in fuel cells? | to help hydrogen and oxygen react efficently |
| why is platinum commonly used? | because it is very efficient at promoting electrochemical reactions |
| what is a downside of using platinum? | it is expensive and limited supply |
| what is the main advantage of hydrogen fuel cells? | they produce electricity with water as the main byproduct |
| what is a major limitation preventing wide spread use? | cost, storage challenges, and infrastructure limitations |
| how are fuel cells different from batteries? | fuel cells need a continuous fuel supply, while batteries store energy internally |
| how are fuel cells different from internal combustion engine? | fuel cells use electrochemical reactions instead of combustion |
| what part of the system causes the biggest losses? | irreversibility's such as resistance and heat transfer |
| if hydrogen fuel cells are so good why don't we use them everywhere? | high costs, hydrogen storage challenges, and limited infastructure |
| fuel cells avoid ___________ but they cannot avoid the second law | combustion |
| hydrogen fuel cells are _________ at the point of use but system challenges remain | clean |
| where are hydrogen fuel cells used in real life? | transportation, power generation, backup power, and portable energy systems |
| why are fuel cells useful in real-world application? | they produce electricity efficiently with water as the main byproduct |
| why are hydrogen fuel cells used in vehicles? | they generate electricity to power an electric motor |
| what types of vehicles use hydrogen fuel cells? | cars, buses, trucks, trains, forklifts |
| why are fuel cells attractive for vehicles? | they have fast refueling times and long driving ranges |
| what is a common example of fuel cell vehicles? | hydrogen-powered cars and public transit buses |
| how are hydrogen fuel cells used in buildings? | they provide electricity and sometimes heat for buildings |
| where might stationary fuel cells be installed? | hospitals, data centers, and commercial buildings |
| why are fuel cells good for buildings? | they provide reliable, quiet, and efficient power |
| why are fuel cells used for backup power? | they provide electricity when the main power grid fails |
| what places rely on fuel cells for backup power? | hospitals, cell towers, emergency facilities, and military bases |
| what advantage do fuel cells have over generators? | they are quieter and produce fewer emissions |
| Where are fuel cells used in portable systems? | In remote equipment, military devices, and research stations. |
| Why are fuel cells useful in remote locations? | they provide power without access to the electrical grid. |
| are hydrogen fuel cells used in space? | yes, they have been used to power spacecraft |
| why are fuel cells good for space missions? | they provide reliable power and produce water as a useful byproduct |
| what industries benefit most from fuel cells today? | transportation, backup power, and industrial material handling |
| how do fuel cells support clean energy goals? | they reduce emissions at the point of use |
Created by:
mccurdyo