Is a pressure tunnel and a penstok the same?

A pressure tunnel and a penstock are not the same, although they serve related purposes in hydropower systems. A pressure tunnel is a large underground conduit that transports water under high pressure from a reservoir to a turbine, while a penstock is typically a smaller pipe that carries water from the penstock to the turbine. Both are designed to maintain pressure, but they differ in their construction, size, and specific functions within the hydropower system.