Octopus Energy
Supplies 100% renewable electricity and gas
Mechanical Engineer
About the job
- A degree in Mechanical Engineering or a closely related discipline is required.
- At least 5 years of relevant experience in an R&D, product development, or test environment is required.
- Demonstrable knowledge of heat pumps, including their operation, operating envelopes, and surrounding hydraulic behavior such as flow, temperature, temperature differential, defrost, and modulation, is required.
- Strong hands-on ability to build, plumb, commission, and fault-find systems independently is required; practical plumbing and pipework skills are essential.
- Experience with hydraulic systems, including pumps, valves, heat exchangers, tanks, pipework, and water-side circuit behavior, is required.
- Ability to instrument test rigs and interpret test data to draw engineering conclusions is required.
- Proficiency with computer-aided design for rig components and prototype parts is required.
- Ability to work independently, use initiative, work on-site in Slough, and operate in a fast-paced R&D environment is required.
- Design, build, and commission hydraulic test rigs and prototype products that integrate with heat pumps, including buffer tanks, hot water cylinders, heat exchangers, circulation hardware, and modulation hardware.
- Assemble and plumb water-side and refrigerant-adjacent systems, including pipework, fittings, pumps, valves, sensors, and controls.
- Instrument test rigs with temperature, flow, and pressure measurement and run structured test campaigns to characterize system and component performance.
- Diagnose and troubleshoot hydraulic, thermal, and mechanical issues on live systems and feed findings back into the design.
- Collaborate with the wider R&D team to iterate designs quickly while balancing performance, cost, manufacturability, and serviceability.
- Produce test plans, build instructions, results write-ups, and design records.
- Experience developing products specifically intended to operate with heat pumps, such as buffer tanks, hot water cylinders, domestic hot water modules, and hydraulic interface units.
- Familiarity with refrigerant-side systems and relevant safety considerations.
- Thermal and fluids analysis skills, including thermodynamic modeling or sizing calculations, to support design decisions.
- Experience setting up, running, and interpreting finite element analysis and computational fluid dynamics analyses on complex systems.
- Relevant trade or industry qualifications, such as plumbing, F-Gas, or G3 unvented hot water qualifications, are valued but not required.
- Experience taking products from prototype into early manufacture.
About the company
Octopus Energy Group supplies 100% renewable electricity and gas to homes and businesses in multiple countries, offering tariffs such as Agile that adjust with wholesale costs. It operates Kraken, an in-house platform that automates billing, customer service, and grid management using AI to balance supply and demand; Kraken is licensed to other suppliers and will be spun off as a separate company. The group differentiates itself through clear pricing, strong customer service, and a scalable energy-technology platform that supports retail, generation, grid flexibility, and EV services. Its goal is to decarbonize energy use globally by making renewables more accessible and by enabling smarter grids, better pricing, and services like EV leasing and demand-response programs.
Company Size
5,001-10,000
Company Stage
Growth Equity (Venture Capital)
Total Funding
$2.9B
Headquarters
London, United Kingdom
Founded
2016
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Simplify's Take
What believers are saying
- Octopus added 700,000 customers in Origin’s March-quarter update and kept growing.
- The Uplight acquisition expands Octopus into eight of America’s ten largest utilities.
- Octopus entered California, China, and Denmark in 2026, widening revenue beyond Britain.
What critics are saying
- Ofgem fined Octopus £1.5 million in July 2025 for prepayment billing failures.
- The Uplight deal needs antitrust clearance and integration across Schneider Electric and Octopus.
- CATL’s blacklisted status invites UK security scrutiny and political delay for Swaptopus.
What makes Octopus Energy unique
- Kraken Technologies reached an $8.65 billion valuation in January 2026.
- Octopus runs Britain’s largest household energy supplier with proprietary trading and billing software.
- Swaptopus with CATL brings truck battery swapping into Octopus’s flexibility platform.
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Benefits
Health Insurance
Dental Insurance
Vision Insurance
Paid Vacation
401(k) Company Match
Parental Leave
Flexible Work Hours
Company Equity
OE Group Share Scheme
Growth & Insights and Company News
6 month growth
↓ -6%1 year growth
↓ -6%2 year growth
↓ -5%UK energy technology companies have raised $16.4 billion across 901 funded businesses, according to Tracxn's Energy Tech UK Report. Investment is concentrating on fewer companies, with annual deal volume falling from 174 rounds in 2021 to 78 in 2025, whilst funding increased from $2.2 billion to $2.4 billion. Late-stage rounds dominated, accounting for $1.6 billion of 2025's $2.4 billion total. Octopus Energy's $850 million Series G alone exceeded the $624 million raised across the entire sector in 2026 year to date. Energy storage systems attracted $622 million over the past year, a thirteenfold increase year-on-year. Charging solutions secured $886 million and clean energy utilities raised $950 million. Seed rounds fell from 93 in 2021 to 37 in 2025, narrowing the pipeline of emerging companies.
Octopus Energy acquires Danish firm BD Energy to enhance its tech-driven power trading and grow renewable energy capacity across Europe.
Octopus Energy and China's CATL have announced a joint venture to build a battery-swapping network for electric trucks across Europe, but the plan faces significant industry scepticism. Analysts warn that resistance from manufacturers and compatibility challenges could derail the initiative. European truck makers including Volvo and Scania are expected to oppose what they view as Chinese encroachment into their market. Critics argue that existing charging infrastructure already functions adequately, making battery swapping unnecessary. The joint venture must overcome substantial hurdles, particularly ensuring the system works across different truck models. Industry observers question whether manufacturers will adopt standardised battery systems required for swapping to succeed, potentially limiting the network's viability across Europe's diverse commercial vehicle fleet.
Contemporary Amperex Technology Co Ltd (CATL), a Chinese firm blacklisted by the US Pentagon as a "Chinese military company", will install battery-swapping stations for electric lorries across Britain from next year. CATL has denied any military links. The company is partnering with Octopus Energy, the UK's largest energy supplier, through a joint venture called Swaptopus. They plan to build 30 battery hubs across Europe by 2035, capable of supporting 300,000 electric trucks. The stations allow drivers to replace depleted batteries in under five minutes. The move could trigger security scrutiny, following a previous case where Chinese wind turbine manufacturer Ming Yang was blocked from UK projects after US national security concerns. CATL already operates over 300 battery-swapping stations in China, where electric models comprise more than 30% of the heavy-truck market.
Octopus Energy and Lunar Energy are offering Texas customers an electricity plan combining a 30-kWh home battery with fixed energy pricing for three years. Participating customers receive the Lunar Energy battery at no upfront cost, paying a $45 monthly subscription fee plus electricity at a flat rate starting at 8 cents/kWh. The batteries will provide grid services and home backup during outages. PowerStore is initially available to a limited number of Texas homes but could expand later. The batteries can pair with solar inverters from six manufacturers, including Tesla, SolarEdge and Enphase. The programme follows similar battery-based retail electricity offerings in Texas. Guadalupe Valley Electric Cooperative recently announced plans to expand its battery partnership with Base Power from 2 MW to 50 MW over the next two to three years.