Buyer Senior Buyer

Senior Buyer Construction - Northampton hybrid role
Infinis is the UK’s leading renewable energy generator of low-carbon power from captured methane. We capture methane gas from landfill sites and disused mines and convert it into electricity. Our expertise also extends to solar farms and battery energy storage (BESS) technology.

This work helps reduce greenhouse gas emissions, which supports the transition to net zero. We’re driving innovation and environmental responsibility. We are looking for an experienced Senior Construction Buyer to play a key role in sourcing and procurement across our utility-scale Solar PV, Battery Energy Storage Systems (BESS) , and EPC/ICP projects. In this role, you will support the whole construction lifecycle by securing high-quality materials and services, optimising costs, and ensuring timely delivery for our significant renewable energy developments.
Reporting directly to the Head of Procurement, you will lead end-to-end supplier sourcing and tendering strategies for construction projects and key components, with a focus on electrical, mechanical and civil packages. You will bring strong negotiation skills, driving cost efficiency while ensuring timely delivery and full compliance with project specifications. You will also oversee contract renewals, evaluate bids, negotiate commercial terms, and monitor supplier performance.

We are in an exciting period of transformation , with a mature pipeline of ‘Ready to Build’ projects and an ambitious target to construct an additional 300MW of solar and 200MW of BESS over the next 5 years, representing £250M of investment.

This role is vital to our growth strategy, offering candidates a chance to make a meaningful impact on our ambitious renewable energy construction projects and future expansion.

Location: This is a hybrid role with the expectation that you will work 2 days a week at our Northampton headquarters, fostering collaboration and flexibility.

Strategic Procurement
Develop and execute procurement construction strategies for Solar PV and BESS projects , covering civils, electrical, and mechanical scopes
Lead detailed commercial negotiations & supply agreements for key materials and components , ensuring cost efficiency, competitive pricing at a line-item level
Prepare cost planning and commercial analysis for major construction packages, ensuring alignment with project budgets and financial targets
Analyse large sets of commercial, supplier, and market data to create sourcing strategies and negotiation positions for specific projects and bids
Maintain cost databases and develop dynamic Excel models to support budgeting and forecasting

Evaluate bids for cost, technical compliance, and delivery schedules and quality
Build dynamic cost models, pivot tables, macros, and dashboards to monitor pricing trends, cost drivers, and supplier performance
Build strong supplier relationships to secure competitive terms and mitigate supply chain risks
Monitor and assess supplier performance against agreed-upon KPIs and SLA’s, implementing corrective actions and escalations to mitigate risks

Commercial & Contract Management
Negotiate supplier contracts and commercial terms with a strong focus on contractual accuracy and risk management, collaborating closely with the Legal team to secure compliant and favourable agreements
Ensure procurement decisions reflect the total cost of ownership
Risk & Compliance
Proven experience as a Senior Buyer in the construction or engineering industry
Knowledge of Solar & BESS products, electrical equipment, construction materials, and EPC project workflows would be beneficial
Familiarity with Maximo and Power BI is advantageous, along with Advanced MS Excel skills for data analysis and cost modelling to evaluate supplier quotations and comparison sheets
Must live within a commutable distance of Northampton to work 2 days a week in the office

Competitive salary with an annual bonus of up to 25% paid annually
~ Domestic solar, battery, and EV charger funding scheme
~ Employee Assistance Program that offers virtual GP appointments
~ Cycle-to-work scheme and eye care vouchers
~ Community volunteering days to give back to the local area
~25 days of annual leave, plus bank holidays
~ Company pension scheme with 6% employer contribution
~ Sick pay eligibility after a qualifying period


We value diversity and inclusion and encourage applications from underrepresented groups . We appreciate your understanding and adherence to our recruitment policy.