What we do

Sonas develop decentralised hybrid energy systems.

Energy Systems need to be secure, affordable and low carbon. The need for heat and power is universal, but we can no longer rely on fossil fuels to supply all our needs. Government policy is to reduce dependence on fossil fuels while still delivering a resilient energy system at affordable costs. This is the so called energy trilemma.


We take a whole system approach integrating supply , intelligent transmission networks and storage with demand side energy efficiency improvements and demand side response .

Intelligent control means that supply and demand are accurately matched. Supply side energy technologies are selected to enable best use of available local renewable resources, and these are supplemented with conventional energy supplies to arrive at a cost effective energy solution.   Demand side with energy efficiency measures and control systems are used to match the supply side profiles of heat and power. Local transmission and storage is used to provide cost effective energy and reduce reliance on centralised grid supply.

Net zero pathways are identifies that will enable offset of residual carbon emissions.


Sonas Hybrid Energy Design & Development

At Sonas we have developed a structure process to deliver projects, we call SHEDD – the Sonas Hybrid Energy Design and Development process.


Stage 0

Project Definition

Project definition generally starts with the identification of need and opportunities. At this stage we will also consider ambition for alignment with the UK government commitment to net zero by 2050 and help define a realistic time frame for the project that is in alignment with this aspiration.


Stage 1

Feasibility Assessment

At stage 1 the energy demand is profiled, together with the likely demand trajectory. This might be driven by demand side action on energy efficiency, or with increased demand from decarbonising heat and transport or from planned new development. Or perhaps all three. At this stage supply side options are identified and opportunities around the project and the site constraints become established.


Stage 2

Concept Design

Stage 2 is concept design where the project takes shape. This will take the form of a reference design together with a road map as to how this will develop with time. In general, unless there is a specific driver or site opportunity, it is likely to be uneconomic to achieve net zero in the very short term. A more likely scenario is a low carbon concept (that exceeds current building regulation) that can be progressively developed to achieve net zero within the desired time-frame. This approach recognises the trajectory of the falling cost of renewables and smart systems as the technology matures and likely increases in carbon cost as we drive towards deep decarbonisation.


Stage 3


The SHEDD tool-kit provides full financial modelling capability for early stage project appraisal. The approach looks at present day and projected costs and allows for the planning of a pathway to netzero.


Stage 4

Detailed Design

This stage is about developing the design. It is important at this stage that adequate provision is made for how the project will develop in future. This will avoid unnecessary costs, reduce investment risk and avoid the risk of generating a stranded asset.


Stage 5

Construction and Commissioning

This stage is where the project is fully realised. Where there is a full-system design, it is important that commissioning is fully co-ordinated, and the control strategies tested. Different elements of the system may be initially commissioned at different times while full system commissioning can only be undertaken sometime after hand-over of specific elements. This means that in many cases provision has to be made for commissioning and optimisation of controls some time after practical completion.


Stage 6


This is where the design and construction team hand-over to the operator. As note above this might be over a protracted period if different elements are to be delivered at different stages. Similarly full handover to operations and maintenance teams may be a sequential and phased activity. This is often the case where there are heat networks and the energy centre and network need to be operational for the early stages of the development while later stages remain in planning and construction.


Stage 7

Operation and Maintenance

As the project moves to this phase, there is work to optimise the control systems, maintain and upgrade the plant and equipment. This is particularly true where the development is on a trajectory to net zero. The pathway for the development may be for progressive upgrade and retrofit. In this stage there may also be a need for a monitoring, reporting and targeting programme to ensure that the project remains on the desired carbon trajectory to net zero.