In a new report, the Science, Innovation and Technology Committee (SITC) said that current efforts are more of a "wish list" than the comprehensive strategy that is required to ensure such capacity is built.
The government's plan to install 24GW of nuclear capacity is almost double the highest installed capacity the UK has ever achieved. Efforts to meet it could involve new gigawatt-scale nuclear power, small modular reactors (SMRs) and advanced modular reactors (AMRs), alongside further development of nuclear fusion, the committee said.
But it would require "substantial" progress on technologies, financing, skills, regulation, decommissioning and waste management, it added.
Nuclear industry witnesses who were interviewed for the report called for a clearer strategic plan than currently exists. This would incorporate commitments from a wide range of stakeholders that are designed to go beyond the lifetime of any single government.
This is because nuclear projects typically take around a decade to build and have an expected operating lifespan of around 60 years. For example, Sizewell C in Suffolk was given £170m last week in order to speed up construction, but is still not expected to start operating until the mid-2030s at the earliest.
SITC also said that the role of recently-launched Great British Nuclear is "unclear" beyond its initial task of running a selection between competing SMR developers.
There is ambiguity over what proportion of the government's 24GW target by 2050 will be met by new gigawatt-scale power plants, as opposed to advanced nuclear technologies.
The committee said a Nuclear Strategic Plan must provide clarity over what proportion of the 24GW target by 2050 will be met by new gigawatt-scale power plants and how much is intended to be met by advanced nuclear technologies such as AMRs and SMRs.
For the 24GW target to be met, it is also estimated that the current nuclear workforce of over 65,000 people will need to more than double, requiring between 75,000 and 150,000 new recruits.
According to the committee, the waste generated by new nuclear power plants is not likely to be "a material factor" in decisions on approving new gigawatt-scale plants. But the report said it is "imperative" to create a clear understanding of how the waste will be dealt with and at what cost early on in the commissioning process.
SITC chair Greg Clark MP said: "The government is right to identify nuclear power as an important contributor to meeting our future electricity needs. It has stretching ambitions to achieve 24GW of nuclear power by 2050. This would be almost double the highest level of nuclear generation that the UK has ever attained.
"The only way to achieve this is to translate these very high-level aspirations into a comprehensive, concrete and detailed Nuclear Strategic Plan, developed jointly with the nuclear industry, which enjoys long-term cross-party political commitment and therefore offers dependability for private and public investment decisions.
"Done right, the UK can be in the vanguard of delivering nuclear innovation, jobs and clean, affordable and reliable energy. But there is now an urgent need to turn hopes into actions."
Speaking to the PA news agency, a spokesperson for the Stop Sizewell C campaign said: "We're appalled that the committee has ignored legitimate concerns about whether nuclear can deliver reliable, affordable electricity."
The group said it supported "the committee calling for the government to publish Sizewell C's cost and value for money, as doing so will expose just how unjustifiable this slow, risky, expensive project is".
A Department for Energy Security and Net Zero spokesperson said: "We have already made clear we will publish a nuclear roadmap and consult on alternative routes to market by the end of the year.
"Nuclear has a vital role to play in reaching net zero and boosting energy security – just last week we launched Great British Nuclear, which will help generate billions for the UK economy and support thousands of jobs."
