[tz] Alberta MLA to table bill aimed at ending DST
Brian.Inglis at SystematicSw.ab.ca
Tue Dec 20 22:58:26 UTC 2016
On 2016-12-20 08:38, Paul Eggert wrote:
> Brian Inglis wrote:
>> Now question is: Do we want to stay on Mountain Standard Time all year,
>> do we want to go to Mountain Daylight time?
> As it happens, a week ago Nicholas Rivers of the University of Ottawa
> published the best work I have seen on the subject of DST-based
> energy savings in Canada. Rivers found that in Ontario, DST reduces
> electricity demand 1.5% during the couple of weeks after the
> transition (he studied transitions, not year-round consumption).
> Like Havranek et al., which I cited a couple of days ago, Rivers
> hypothesizes that DST-based electricity savings is most pronounced
> at high latitudes, and notes that he does not estimate the costs of
> DST (e.g., due to increased traffic accident rates).
Havranek et. al. I found a wee bit annoying as it made it clear that
there was no benefit at lowest and highest latitudes, but did not
provide sufficient data on numbers and locations to nail down the
"Goldilocks" latitudes where it does provide a benefit to say 35-50.
My own experience here is that the dates are far enough from the
equinoxes that we drive to and from work into the sunrise and
sunset for two months instead of one, so what we lose in spring
we gain in fall, but still don't see daylight at home except April
to September, and the days are short enough at the changes that
energy consumption likely depends more on weather than time.
Given that the UK is also all above 49N I can sympathize with
the Scots, most of whom live at or above 55N, complaining about
the time change impact.
> Rivers N. Does daylight savings time save energy? Evidence from
> Ontario. 2016-12-13. SSRN. https://ssrn.com/abstract=2772048
> Cash C. Spring forward, fall back ... screw up? Reconsidering
> Alberta's clock revolt. National Post 2016-12-19.
Most of the eastern Canadian population is just north of the border
on the Great Lakes and St Laurent, well south of the 49N western
border, nearly 10 deg S of western cities, uses a lot more domestic
electrical heating and air conditioning with probably lighter
insulation, than western areas which use electricity mainly for
industrial processes and air conditioning for commercial premises
with heavier insulation which helps in both winter and summer
extreme temperatures ("it's a dry heat|cold").
Rivers seems to show that electricity demand is most highly
correlated with high temperatures and presumably air conditioning
load, possibly because he seems to be using Toronto as a proxy for
Ontario, despite its size, for some variables, and does not seem to
control for the reduction of demand by high costs driving dependent
industries out of province, generation facilities going offline for
maintenance reducing supply, wind generation providing supply greater
than demand driving prices negative, commercial and industrial load
shedding and peak to off peak consumption shifts by heavy users
during high demand and cost, and contingent generation facilities
brought online to take advantange of high demand and prices i.e.
the drivers of consumption.
For tariff reasons, heavy lighting consumption is tracked separately
from domestic, retail, light and heavy commercial, and industrial
users, so it should have been possible to look at consumption and
calculate differences for each group, and look at factors behind
differences more closely.
I find it difficult to believe that very predictable lighting demands
would be so heavy as to allow a 1.5% reduction of overall provincial
demand without other factors being in play - I could believe it for
Toronto during clear sunny weather, but across a province spanning
the Great Lakes and N to Nunavut in early spring, I have grave doubts
as to the likelihood of that being possible without further checks
on the assumptions.
Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada
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