DC Treasurer Andy Sutton prepared a formal response to the consulation on Low carbon housing on behalf of Design Circle and the Royal Society of Architects in Wales.
The National Assembly of Wales
consultation on low carbon housing closed on 23rd November , and below is the
response to one of the nine questions they posed:
What role can housing can play
in Wales’ low carbon transition, including the potential positive impacts on greenhouse gas emissions?
The transition to a low carbon
economy can be fundamentally supported by the right strategic choices being
applied to housing in Wales. These choices must consider the following shifts;
- from gas and other fossil fuels for heating, with a significant
proportion to electricity
- from fossil fuel for transport, most likely also to electricity for
the majority
- towards greater renewable electrical generation for the foreseeable
future (<50 years)
- towards alternative/additional power sources in the “unforeseeable”
future (>50 years)
- towards a likely +2.8±1˚C warming and a wetter, warmer
climate
The combination of these
probable shifts is a more variable generation of electricity, combined with at
least a six-fold increase in electrical demand overall (this is heating alone,
not including transport), compounded by demand peaks and supply peaks fundamentally
not aligned. This will be occurring in a climate more inclined to wetter, more
severe weather conditions, but with no change on the levels of solar irradiance
(warmer does not mean sunnier).
The right strategic choices
must also consider known factors about housing in Wales that are unlikely to
shift significantly, which include;
- Wales has the oldest housing stock in the Western world, and at
rates of renewal and given the levels of economic activity underpinning,
this appears likely to remain true
- UK private home owners have a poor general record for maintenance
of their properties, and an SME industry that delivers much of this work
in a lightly regulated or self-regulated fashion
- Despite increasing energy efficiency of individual devices, the
profligation of the number of devices results in an occupancy energy
demand that is unlikely to significantly reduce.
The logical strategic role for
housing in Wales’ Low Carbon future can therefore be summarised as RBG –
Reduce, Balance, Generate.
- Reduce. With electrical demand soaring due to transport and heating loads
switching to electric, housing must ensure it is placed to reduce the
demand for energy from these causes first and foremost. This means homes
built in the right place to minimise transport energy demands as well as
with excellent fabric performance to reduce their heating demands.
- Balance. Housing’s long life and predictable use align with their use to
help shift the energy demands to better align with the energy generation.
This can be achieved through technologies or fabric solutions (such as
thermal mass) to shift heating demands to match supply, but additionally
to include storage for balancing electrical demands (with batteries having
less need to be lightweight or small compared to those in electric
vehicles). The long life of our homes also provides a means to balance
already present carbon emissions through locking atmospheric carbon into
construction materials, as well as through associated landscaping &
tree cover that can be included within residential development.
- Generate. Lastly, where appropriate ownership or maintenance models can be
demonstrated, opportunist generation of energy across our housing stock is
capable of making a worthwhile contribution to energy generation for Wales.
However, this must be done in the context that the vast majority of these
homes will outlive the energy generation system mounted on them (even
assuming proper and effective maintenance is undertaken), and that these
homes will need to continue to be a desirable and pleasant home after
this.
In addition to the above, it
is important for the strategic role of housing in Wales’ Low Carbon future to
be implemented beyond the scale of the individual home. Achieving any of the
RGB steps is less technically and economically efficient if done on a case-by-case
basis: this approach requires sizing elements to accommodate ‘worst case’
instances that are likely to occur very infrequently, but cannot be ignored.
This increases material usage and prices whilst still not providing redundancy
to individuals. Hence the individual home approach is both uneconomic and
inefficient, whilst if suitable professional ownership or maintenance models
are not required, also risks placing the operation and maintenance of an
increasing part of our national energy generation in the hands of untrained,
unfunded and uninterested homeowners.
Homes must therefore be
thought of as communities of ‘nodes’, where ‘worst case’ events can be
distributed across the locality. This approach must be applied to reduction
(where some homes will not be able to reduce as far as others), balancing
(where some may help balance others), and generation (where energy generation
can help local homes not generating at that time). Whilst taken in the context
of UK’s legal, energy and property ownership frameworks, this is acknowledged
as a challenging model, it does represent the most efficient means of
delivering the low carbon outcome.
The full response will shortly be on the Welsh Assembly website, or drop
Andy a line for a copy.