(Gerard Wynn is a Reuters market analyst. The views expressed
are his own.)
By Gerard Wynn
LONDON, Sept 30 Britain's plan to raise speed
limits will make little difference to emissions but is
incompatible with setting demanding climate targets and
contradicts the government's own advice.
The government's Department for Transport (DfT) announced on
Friday that it wanted to raise the top limit on open roads to 80
miles per hour from 70 mph.
The gain in fuel efficiency from buying a model made in 2005
compared with 2000 is about three times the gain from driving at
70 mph rather than 80 mph, DfT data show.
But the idea isn't to stand still: the time for raising the
limit was 1970 when Britain discovered oil in the North Sea and
climate change was unheard of.
Now Britain's oil reserves are dwindling while it has a
stretching target to halve carbon dioxide (CO2) emissions by
2025 compared with 1990 levels.
Its plan to raise speed limits runs against the advice of
its own, UK-funded Energy Saving Trust and statutory climate
adviser the Climate Change Committee (CCC), and it breaks its
own to holidaymakers two months ago.
The DfT asked drivers embarking on their summer holidays in
July to: "Watch your speed. Fuel consumption increases
dramatically with speed: At 85mph a car uses approximately 25
percent more fuel than at 70mph, and at 70mph approximately 10
percent more than at 60mph."
The inconsistency suggests incoherent decisions on
environment by the Conservative-Liberal Democrat coalition which
pledged to be the "greenest government ever".
The DfT has compared CO2 emissions with speed for cars which
meet 2000 and 2005 efficiency standards. The improvement in
efficiency from buying a new model far exceeds that of driving
at 70 mph rather than 80 mph for any given model, at about 15
grams of CO2 per kilometre compared with about 5 grams.
But the point is to drive down emissions and fuel
consumption, and it makes no sense to erode even a small part of
gains from a newer model by driving faster.
The government's climate adviser, the CCC, said in June that
raising the limit to 80 mph could result in up to 3.5 million
tonnes extra carbon dioxide (CO2) emissions per year, or 3
percent of last year's CO2 emissions from transport.
The CCC recommended the government enforce the existing, 70
mph limit better - rather than raise it - and roll-out
"eco-driving" training to help meet CO2 targets.
According to the Energy Saving Trust, in part funded by the
Department for Transport, more efficient, eco-driving means
avoiding acceleration in cities and excessive speed on open
Many countries already have an 80 mph (130 kilometres) speed
limit, but raising to that level now makes no sense.
For the next several decades most cars will be driven by
conventional internal combustion engines, rather than electric
vehicles (EVs) which sold just 5,222 EVs in all Europe in the
first six months of this year, according to the research firm
JATO Dynamics, or 0.07 percent of all cars.
Gains in fuel consumption therefore rest on improving
conventional engines and driving them carefully.
(Reporting by Gerard Wynn)