The plant has a construction cost of §100,000 and a default monthly operating cost of §10,000. A newly-built and fully-funded hydrogen power plant generates 50,000 MWh of power, giving it the highest production capacity by far. The plant produces no pollution.
In order to be able to build the plant, there must be at least 4,000 high-tech industrial jobs within the city, as well as a demand for at least 30,000 MWh of electricity, between the city and any neighbor deals. If SimCity 4: Rush Hour or SimCity 4 Deluxe Edition is played, the plant is unlocked as a reward for the completion of a U-Drive-It mission. The plant can also be unlocked through the 'you don't deserve it' cheat.
The ability to cleanly produce 50,000 MWh of electricity makes this a tempting plant to build in any city. For comparison, it would take over eight coal power plants running at capacity to equal the capacity of this plant. The construction of alternative power plants may consume possibly scarce land, and many plants generate undesirable pollution.
However, the convenience of a high-capacity clean electric source is outweighed by the massive monthly cost of operating the plant. At a cost of §0.20 per MWh, the Hydrogen Power Plant is tied with the Solar Power Plant as the second-most expensive power plant to operate. To compare, a Coal Power Plant can generate 6,000 MWh on only §250 per month, meaning the cost of running nine Coal Power Plants (generating a total of 54,000 MWh) is only §2,250 per month, compared to the §10,000 a month it costs to operate a single Hydrogen Power Plant.
Many cities with tight budgets may not be able to maintain a profit while running hydrogen power plants. Even in cities with a healthy surplus, it is much more inexpensive to either build coal power plants within the city, or to build them in a neighboring city and import the power.