[tz] Alberta MLA to table bill aimed at ending DST

Brian Inglis 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.
> http://news.nationalpost.com/full-comment/colby-cosh-spring-forward-fall-back-screw-up-reconsidering-albertas-clock-revolt

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

More information about the tz mailing list