This is an emergency and the policy must be tighter. See previous comments on low carbon & wording style. This policy has too many get-out options - they should, sorry, must, be removed.

'unless the costs or configuration of the development can be demonstrated to make this unviable or impractical.' This should be removed so developers are not allowed a 'get out of jail free' card regarding fossil fuels. Non fossil fuel sources need to be used as widely as possible to make their use viable and practical, otherwise they will remain niche and expensive. Developers must be directed to use them from now onwards.

A sensible approach which does allow alternatives in genuinely unviable cases.

Sets out a requirement for the inclusion of an energy statement, with consideration of onsite renewable energy generation, use of heat sources and networks, or other available low carbon energy sources. It also states the use of fossil fuels should be avoided unless it can be clearly demonstrate this will be unviable (from a capital cost and operational point of view), or available options will not fully meet the energy demands. It is noted that this Policy will apply to full or reserved matters applications.
In the first instance the policy as it is written does not specifically set any target for the deployment of zero or low carbon energy sources but requires options to be considered and where possible installed. The supporting text shows it is the intention for developers to utilise onsite generation or low carbon systems to reduce emissions however it is not clearly set out in the policy that this is the case.
While we recognise there is a need to move away from fossil fuel use from 2025, and to help meet the UK zero carbon target. As noted in the responses to Section 1, and Policy NZC2A, bringing this requirement forward is not currently viable, nor is the supply chain adequately developed to deliver these requirements effectively. This is a large part of why the Future Homes Standard has an implementation date of 2025 to allow these issues to be resolved, and therefore continues to allow the use of fossil fuels. In addition the FHS is clear in not setting prescriptive requirements on how developers meet both the interim and full FHS standards.
In this context it is considered that the policy should be amended to allow development to continue to meet the requirements of the FHS in line with the Governments guidance, with provision made to future proof development as set out in Policy NZC2(D) and enable net zero ready development.
It is noted that both Policies NZC2(A) and NZC2(B) will apply to both new full applications and reserved matters applications. While we agree in principle with the creation of new policies which apply to new applications, provided this follows the appropriate process, applying new policies to existing outline permissions and reserved matters applications is not appropriate.
Reserved matters applications are required to meet the conditions attached to an outline planning permission and agreements made as part of an S106 agreement. In the case of an existing outline planning permission this will have already gone through a process of design, viability, and negotiation with the Council around S106 payments which will have been based on the site land values and requirement in place at the time of the permission. This will not have considered these additional policies and it is therefore not possible to retrospectively apply new policies to an existing permission without renegotiation or consideration of the viability impacts on development.
As noted in the response to Section 1 the requirements have already been shown to be unviable for the majority of residential development and additional requirements at this stage of a sites application and design process will not be viable.
In this context we would suggest the removal of the requirement for Policies NZC2(A) and NZC2(B) to apply to reserved matters applications, and instead applied at the outline planning application stage. If the Council insists that there will be a requirement at the Reserved Matters stage, there will need to be a transition period, where Reserved Matters applications will not be considered against these additional policy requirements, unless the associated outline planning permission was received after the DPD is published.