New Scientist - 09.11.2019

(Grace) #1
9 November 2019 | New Scientist | 19

“There is a tendency for people
to think ‘I need solar panels or a
whizzy app to control my heating’,”
says Russell Smith at energy-
efficiency consultants Parity
Projects. Try to resist the urge,
he says. Instead, if you are looking
at upgrading your existing home
to cut carbon emissions, Smith
recommends finding a local
company to do an impartial energy
assessment of your property to
see all the possible opportunities.
The priority should be to reduce
the need for energy. A typical
home uses 65 per cent of its
energy for heating, so insulation is

key. “Insulating all external walls,
floor and roofs, then upgrading
windows and plugging all of the
gaps to reduce draughts has a
massive impact on bills and more
so on comfort,” says Smith. Once
it is airtight, you then need to keep
an eye on ventilation to maintain
air quality, though, he adds.
Energy efficient appliances and
lighting are next. Only once you
have done everything you can
to reduce demand should you look
at a low carbon heat source – like
a heat pump – or generating your
own energy, such as through solar
panels, says Smith.

How to green your home


Solar panels may not be
the best way to cut your
carbon emissions

to build homes that are net-zero
compliant, water efficient and
don’t overheat. The problem
we have is with the skills and
industry.” Compliance regimes for
new homes, enforced by thinly
stretched local authorities, aren’t
fit for purpose, she adds. Hill also
believes that the new standards
should be introduced before 2025.
Still, the future homes rules
have been broadly welcomed,
even if they could be tightened up
in places. “There’s a general thing
here about moving away from
fossil fuels, which is to be
applauded,” says Lowes.
There may be grumbles in some
quarters about induction hobs
and people missing gas boilers,
but Lowes thinks there will be an
inevitable movement away from
combustion in homes, not just
for climate change reasons but
because of concerns over indoor
air pollution. “Longer term, the
idea of burning stuff in the house
will be seen as completely daft.” ❚

For more on what we need to do to
tackle climate change, see page 22

batteries are expensive. You don’t
need solar power or a battery but
it’s nice to have,” says Lowes.
The Home Builders Federation
trade body says it welcomes
standards on carbon emissions,
but argues that the government’s

proposals would be very
challenging and require a lot
of work on supply chains. Such
concerns can have an impact.
In 2015, the government shelved
zero-carbon home standards
a year before they took effect,
in a sop to developers.
Hill questions why the UK
construction industry should
find the rules a challenge,
when a gas-reliant country
such as the Netherlands has
already introduced rules
banning gas boilers without
it causing problems.
“From our perspective, we
believe the technology exists now

CHRIS HOWES/ALAMY REELDEAL IMAGES/ALAMY STOCK PHOTO; GETTY IMAGES


lock-in carbon, and “green roofs”
covered in vegetation, providing
a natural form of insulation to
reduce energy consumption.
Although 2025 is the key date,
the government is proposing
an interim strengthening of
regulations next year. That won’t
force the switch to greener
heating, but promises a cut of
31 per cent on carbon emissions
and more than £200 off average
annual energy bills for new builds,
versus rules today. Solar panels,
already on the roofs of nearly
a million homes, would be one
way to do that, officials suggest.
Hill says there is definitely a
role for solar panels, but they are
no substitute for a low-carbon
heat source. “You have to look
at how you decarbonise your
heating and that is what delivers
the bulk of your savings.”
Home battery storage devices,
which can store electricity from
solar panels and exploit off-peak
energy tariffs, are expected to be
niche initially and are unlikely
to be standard in new homes.
“It comes down to the economics:

▲ Space cookies
Astronauts will be baking
cookies in a new space
oven as a PR stunt. Looks
as if it worked, given that
we are writing about it.

▲ Pet face-swap
Ever wish your dog was a
lion? Obviously not: think
of the furniture. But if you
insist, NVIDIA has made
a photo app that morphs
the face of one animal
into another.

▲ Vampire bats
Creatures of the night are
generally unfriendly, but
it turns out vampire bats
form close relationships
in captivity and retain
them in the wild.

▼ Climate meeting
Greta Thunberg has had
to beg a ride back across
the Atlantic, as a major
climate summit is moving
from Chile to Spain.

▼ NHS pagers
Pagers used by the UK’s
National Health Service
are leaking medical data
over radio waves, possibly
to the 1980s, where
pagers belong.

Working
hypothesis
Sorting the week’s
supernovae from
the absolute zeros

More Insight online
Your guide to a rapidly changing world
newscientist.com/insight

“We don’t currently know
how people are going to
react to not being able
to install gas boilers”
Free download pdf