Solar Design Engineer

Job Description Solar Design Engineer – Cardiff Up to £50,000 basic Unify HQ is working with one of the UK’s fastest‑growing renewable installation companies, as they continue to scale their clean‑energy operations, they are now seeking a Solar Design Engineer to help deliver high‑quality, compliant and efficient Commercial (and occassional residential) solar and battery systems across South Wales.

You’ll take ownership of the technical design, specification and quality assurance of Commercial solar PV and battery installations. This includes producing compliant system designs, supporting installers with technical queries, and ensuring every installation meets the relevant standards, electrical regulations and manufacturer requirements. It’s an excellent opportunity for an experienced solar designer or electrically‑skilled engineer looking to step into a more technical, process‑driven role within a rapidly growing renewable business.

• Lead the end‑to‑end technical design of commercial solar PV and battery systems
• Produce compliant PV layouts, inverter/battery specifications, cable schedules and SLDs
• Validate roof plans, shading analysis and system performance estimates
• Ensure all designs meet G98/G99/G100 and DNO requirements
• Provide technical guidance to installers, project managers and customers
• Troubleshoot design issues and refine system specifications based on installer feedback
• Improve internal design processes, templates and technical documentation
• Stay up to date with solar and battery technologies, standards and best practice

• Proven experience designing and specifying solar PV and battery systems
• Strong understanding of electrical installation practices and BS 7671
• Experience working with MCS standards for PV and storage
• Confident interpreting surveys, photos and roof plans
• Ability to identify risks, compliance issues and optimisation opportunities
• Excellent attention to detail and a methodical approach
• Strong communication skills and confidence advising installers
• Comfortable working in a fast‑moving, scaling environment
• Full UK driving licence (site visits)
• Experience with PV design software (PVSol, Helioscope, Open Solar, etc.)

• Battery commissioning or manufacturer training (Giv Energy, Tesla, Solar Edge)
• Experience leading teams or managing technical workflows

• up to £50k salary
• Possibility for Company vehicle (depending on experience)
• 28 days holiday (including bank holidays)
• Opportunity to shape processes in a fast‑growing renewable business
• Supportive, modern and inspiring working environment