The Hualong One (also known as Hualong 1 and HPR1000) is a pressurized water nuclear reactor with features merged from reactors made by the China General Nuclear Power Group (CGNPG) and the China National Nuclear Corporation, and originally derived from a French design.
Hualong One merged design Wikipedia
With little fanfare last week, the Chinese designed HPR1000 (previously Hualong-1), pressurised water reactor, cleared the first of four stages in the General Design Assessment (GDA) administered by the UK Office of Nuclear Regulation (ONR). China General Nuclear (CGN) proposes to build 2 reactors of this design at the Bradwell site in England, in partnership with French state-owned EDF that currently operates all UK commercial reactors.
This guest post by Andy Dawson gives a preliminary overview of the design focussing on safety systems.
UK HPR1000, Generic Design Assessment (GDA) website 
CGN and EDF, through their joint venture company General Nuclear System Limited, commenced the Generic Design Assessment (GDA) process for the UK HPR1000 in January 2017.
General Nuclear System has been established to act on behalf of the three joint requesting parties (CGN, EDF and General Nuclear International) to implement the Generic Design Assessment of the UK HPR1000 reactor; more information on the each of these companies and the structure of General Nuclear System can be found on the about us page. For practical purposes, General Nuclear System is referred to as the ‘UK HPR1000 GDA Requesting Party’.
This website has been set up to publish information on the HPR1000 nuclear reactor design that is currently undergoing assessment by the UK nuclear regulators – the Office for Nuclear Regulation and the Environment Agency. You can find out more information about the process on our GDA process page.
On 15 November 2018, the regulators concluded that the information submitted by General Nuclear System during Step 2 was sufficient to allow the start of Step 3. As part of the GDA process we continue to invite you to comment on the HPR1000 reactor design and the regulatory submissions that we make to the regulators.
Comments received by 25 October 2019 have been considered as part of the ONR’s assessment of Step 3. The Environment Agency will continue to accept comments for this step after this date and will be consulting on its findings so far, in due course. More information is available on the EA website.
Within this site you will find information on the HPR1000 reactor technology, design, safety and environmental features. You can also access the range of technical documents that will be submitted to the regulators throughout the process in our document library.
"UK HPR1000 moves to final design assessment stage", World Nuclear News , 13 Feb 2020
The UK HPR1000 is the Hualong One design that General Nuclear Services - a subsidiary of EDF and China General Nuclear - proposes to use at a prospective new nuclear power plant in Bradwell, England.
"The objective for GDA is to provide confidence that the proposed design is capable of being constructed, operated and decommissioned in accordance with the standards of safety, security and environmental protection required in Great Britain," Ana Gomez-Cobo, ONR’s head of UK HPR1000 regulation, said.
"Our assessment to date has not identified any fundamental safety or security shortfalls that would prevent us issuing a Design Acceptance Confirmation (DAC) for the UK HPR1000 design. However, we have identified a number of areas for which further substantiation is needed from the Requesting Party; these have been captured as Regulatory Observations. Although progress so far is encouraging, a lot of work by the Requesting Party is still required. We will continue to rigorously assess safety and security submissions throughout Step 4 of GDA."
The GDA is a voluntary process for reactor vendors - it is policy rather than law - but it is a government expectation for all new-build projects in the UK. In January 2017, the British government formally requested regulators start the process for the UK HPR1000. The regulators, who have said they aim to complete the GDA of the UK HPR1000 in late 2021, have published a report summarising their Step 3 assessment here.