A round table discussion last
week on decarbonisation of the heat sector was a reminder of just how large and
complex a question the future of UK domestic heating is set to become. A
paradox of the sector is combination of major technology choices at one end of
the chain, with all the potential concerns of parish pump politics (not intended
as a disparaging term) at the other. Sourcing the heat in the first place has
multiple competing options and poses huge strategic decisions across the power
and gas industries; these include modular nuclear, heat and other storage
technologies and linkages to carbon capture. But there are also distribution
issues including the demand heat pumps can place on local power networks. And downstream
distribution of heat in district heating schemes is dominated mainly by the
relatively low tech problems of digging up streets, laying pipes, retrofitting
homes, persuading or compelling householders, and a myriad of particular local issues
and considerations which historically at least are associated firmly with local
authorities and their skills and expertise. Our round table focused on the
latter and on district heating in particular.
The
Big Picture
Most scenarios for a low
carbon future, and, post Paris, especially a zero carbon future, expect
domestic heat needs to be met predominantly from innovations such as heat pumps
installed for individual households, or through communal systems involving the
sourcing of heat from combined heat power production, involving various thermal
generation technologies. These include modular nuclear and fossil plant with carbon
capture, combustion of waste products, and some geothermal and other sources. A
fuller discussion of the heat sector from this perspective is given on the [DECARBONISING HEAT] page (button at the
top of this page).
The future of heat delivery,
in terms of these “big picture” options, is very obviously bound up with the future of
the power sector, but it also has a local scale at which the major transformation
has to be implemented, potentially affecting every household in the country. Key
points that emerged both from what was discussed at the round table, and what was
not discussed, were several.
Immense
scale of what is involved, compared to UK experience to date.
DECC evidence suggests there
are at present some 1750 district heating networks in the UK, with two thirds
of these classified as small (less than 100 households), with an average of 35
households per scheme. There are only some 75 “large” networks with more than
500 households, and the total number of households connected to a network is
around 220,000, or less than 1% of all households. So the UK does have some experience
in developing and maintaining these networks, but the scale is tiny compared to
our expectations for the future. Even defining
“large” as 500 households is revealing in this context. In Denmark the CTR
scheme for central Copenhagen serves 275,000 households.
To put this in perspective
there are some 27 million households in the UK, so the full decarbonisation of
the heat sector by 2050 is likely to require installation or retrofitting of low carbon solutions (heat network or
individual property solution) to around 20,000 households a week over about 25
years, assuming a starting at some point in the 2020s. In other words this implies an entirely
different scale of operation from anything of which the UK has any past experience.
A
future district heating industry will develop a very different culture.
The dominant culture in the
management of heat networks reflects (mainly) a history of post World War II local
authority reconstruction schemes, together with some opportunistic exploitation
of specific sources of waste heat from power station or other industrial
schemes. The positive benefits of utilising “waste” heat combine with some of
the social objectives associated with local authority schemes, including
keeping the costs to householders as low as possible. One of the benefits of “waste”
heat is that it has frequently been provided at very low or no cost to the
scheme.
The low carbon objectives
which will underpin the future of district heating will create some very different
economic conditions. The supply of waste heat per se is really very limited,
although the future will most likely include purpose built installations built
specifically with the dual purpose of providing city-wide heating and power to
the national system. But schemes will have to fund significantly higher heat
costs, as well as infrastructure, and the cost of heat is likely to be significantly
higher than it is for today’s householders who enjoy a gas supply.
The economics of large schemes
depend on scale. Getting to a reasonable average cost will depend on achieving near
universal penetration in high density urban populations. This will accentuate the
problems of collective choice for heating and may introduce elements of
compulsion.
Taken together with the sheer
scale of the district heat undertaking, the challenges for traditional management
structures and assumptions in the heat sector will be immense.
Cost
of capital again a critical issue.
Once again, and as in the
power sector, the capital requirement will be very large. I have emphasised on
many occasions the fact that infrastructure projects “ought” to be considered
as low risk, low cost of capital investments. But this requires careful
attention to the structuring of the funding arrangements and may require
substantial public sector guarantees and significant local government
borrowings, another major cultural shift. This is increasingly accepted but it
is a necessary condition for the transformation of the sector at a reasonable
and affordable cost.
Roll
out in conjunction with energy efficiency
One of the most fundamental obstacles
to introducing large scale district heating is the physical disruption to the
householder. The same issues promote inertia in introducing household level
measures for energy efficiency. Given that energy efficiency is a necessary
part of overall heat strategy anyway, in order to bring heat loads down to
manageable levels, then coordinating and integrating the rollout of low carbon district
heat with energy efficiency measures makes a lot of sense.
Regulation
Finally we can foresee some
new and challenging questions for energy regulation, and a considerable
political overlay.
First, this is another sector dominated
by fixed infrastructure, ie network, costs. There is considerable scope for
alternative approaches to how those are recovered from consumers, eg a fixed
charge per household or an averaging over all kWh of energy consumption. This
will include the question of whether heat metering is feasible and desirable.
Second there will almost
certainly be a huge variation in actual costs between different schemes and
geographies. This may provoke political demands to “even” out the costs to
householders, avoiding the “postcode lottery”.
Third, initial concentration on
high density urban housing will ensure that social policy issues come rapidly to
the fore. Will this lead to new approaches to fuel poverty questions?