Security Architect in London

Sizewell C’s business is to design, finance, construct, commission, operate, maintain, and eventually decommission the nuclear power plant and related infrastructure at Sizewell C in Suffolk. Overall, whilst the Company is in the construction phase, the Boards’ principal focus is on the development and construction of Sizewell C on time, on budget and to the highest quality and safety standards. The Company is maturing to meet all these requirements.

Sizewell C is economically regulated by OFGEM under the Regulated Asset Base (RAB) model similar to other UK electricity distribution networks and Thames Tideway. Sizewell C construction strategy is to replicate the design of Hinkley Point C, using the majority of the same supply chain, but innovating in the way it is delivered to achieve savings in time and cost of around 20%. The CCO will need to be guided by and incorporate lessons learned from the Hinkley Point C commercial delivery to achieve Sizewell C’s ambition.

Following Financial Completion and Revenue Commencement, Sizewell C is fully funded and is owned by; The Secretary of State for Energy Security and Net Zero representing HM Government, La Caisse, Centrica, EDF and Amber Infrastructure. Sizewell C is entering an exciting phase of growth as we mature into an independent organisation and continue building one of the UK’s largest and most important energy projects. We are now recruiting the below position.

Location: Based in London on a hybrid basis with travel to Suffolk as required.

Contract: Permanent, full-time.

Salary: Circa £80,000 dependant on experience, plus benefits

Closing Date: Friday 18th September 2026

Benefits include:

• Salary: Competitive (depending on experience)
• Bonus: 5% annual target
• Holiday: 28 days + bank holidays
• Pension: Market-leading (up to 7.5% employee / 15% employer)
• Hybrid working & ongoing professional development

About the Role

We are seeking an experienced Security Architect to lead the design and governance of secure technology solutions across the Sizewell C organisation. Working within a highly regulated and safety critical environment, you will ensure that security is embedded into systems, infrastructure, cloud platforms, applications, and operational technology from inception through delivery. You will collaborate with Cyber Security, Enterprise Architecture, Engineering, Infrastructure, Digital, and third-party suppliers to define security standards, assess risk, and support the delivery of resilient and compliant technology solutions.

About You

• Proven experience in a Security Architect or senior cyber security role within large, complex organisations
• Extensive knowledge of security architecture frameworks, cloud security principles across Azure and/or AWS, network and infrastructure security, Identity and Access Management (IAM), Zero Trust and secure access models, and security monitoring and threat management technologies.
• Experience designing secure enterprise and operational technology environments
• Knowledge of cyber security standards and frameworks such as ISO27001, NIST, CIS, or IEC 62443
• Strong stakeholder management and communication skills
• Ability to balance security, operational, and business requirements

Why Join Us?

• Be part of one of the most important low-carbon energy projects in the UK.
• Work in a mission-driven environment that values innovation, integrity, and long-term sustainability.
• Competitive salary, comprehensive benefits, and opportunities for career development.
• Flexible and hybrid working options.

Behavioural Competences

• Humility: Recognise the value brought from different cultures and experiences. Be open to others' points of view and ideas, be willing to debate and to compromise.
• Positivity: Positively challenge poor quality and performance. Identify solutions at the lowest possible level. Encourage tier 1s and others to bring new ideas forward.
• Respect: Value the rules and environment in which we operate. Give and receive feedback with respect. Embrace and engage with new people and ideas. One team, working closely together and helping each other. Empowered teams always looking forward. Shared responsibility for delivering the project outcomes.
• Clarity: Communicate clearly and consistently. Promote collaboration and team alignment. Drive simplification at all levels.

When joining Sizewell C, you may wonder why you are contacted by colleagues with an EDF email or see the EDF logo on portals that you access and/or documentation you receive; this is because we have partnered with EDF for the provision of a number of support services whilst we complete a successful transition out of the EDF group.

At Sizewell C we encourage and embrace diversity and how it can improve our experience and performance at work. It is a requirement that those who join us have the right to work in the UK. Whilst sponsorship may be a possibility that we can explore, we are fully committed to local recruitment where possible, and those already holding the right to work in the UK.

To be appointed to this role, you will need to meet the criteria for Security Vetting, which will, ordinarily, require you to have been a resident of the UK for at least three of the past five years.