The indoor environment affects your health, here’s what you can do about it:

The indoor environment affects your health, here’s what you can do about it:

A snake plant, pictured above, is one of the many plants that can naturally filter your air.  Near the end of this article there’s a link to six other plants that are also great air filters.

Making an indoor environment healthy for human occupants is not as simple as it seems.   There are Continue reading

Electric vehicles are coming – and that’s a good thing

Electric vehicles are coming – and that’s a good thing


Electric vehicles will have a positive environmental impact but that’s not always what you read. The point of this blog is to clear that up.

Renewables and electric vehicles (EVs) are shaking up long-established industries but there’s still a lot of misinformation spread around.  Online and even in our own Toronto papers I’ve seen some surprising… falsehoods about electrics.  From what I’ve seen most of it’s based on incorrect assumptions or outdated information.  For example did you know that since 2010 battery costs have fallen 80%, a full 7 years faster than expected?  Or that companies like Mercedes expect 25% of their sales to be electric by 2025?  Or that Tesla is targeting production of 500,000 electric vehicles in 2018?  There’s the Chevy Bolt EV out now, the Tesla Model 3 coming soon, and nearly all major manufacturers have now committed to producing long range EVs.  The future is rapidly approaching. (Pictured above: Longer range mass market electric vehicles – Telsa Model 3 and Chevy Bolt.  Images from Tesla and GM.)


So why is this a good thing?

Here are the facts:


1.Electric car batteries can, and are, being recycled.

There are articles that decry “electric car batteries are toxic sludge”, but those claims are unsubstantiated and unsupported.  Tesla has published a good deal of information about their batteries and recycling.  First, their batteries are RoHS1 compliant and fully recyclable.  RoHS refers to the restriction of hazardous substances directive for electrical and electronic equipment, adopted in 2003 by the EU.  Tesla also recycles their batteries 100% within Europe and at ~60% in the US, according to their blog.   Tesla is also building a recycling facility at their Gigafactory in Nevada.  Seems like there won’t be much toxic sludge to worry about.


2. Our electricity grid is actually pretty clean (from an emissions standpoint)

The myth “you’re using fossil fuels to power your electric car” is false.  Let’s look at where we live, with an Ontario electricity mix that includes no coal and only 10% from natural gas.  It’s mostly nuclear and hydro.  Canada on average is also looking good with 63% coming from hydro alone.  That’s a lot of carbon free power.

The USA average doesn’t look as good but it’s improving all the time (and we will see later that EVs are still the better choice).  There we see 33% of electricity from coal, 33% natural gas, 20% nuclear, 6% Hydro, and 7% from other renewables.  Still every year more coal plants are shut down and more renewables are being installed.  In 2015 7.5 GW of solar was installed in the US and in 2016 a total of 14.1 GW.


3. Using electricity to power your car is more efficient than your gas or diesel

I recently read an article that said “burning a fossil fuel to power an electric car is nowhere near as efficient as burning that fuel to power the car directly”.   That’s simple not true but more importantly that’s not even a real scenario.  Just look at the electricity mix above, fossil fuels are only part of it.  Even in the US where fossil fuels use is much higher, natural gas is a cleaner, lower carbon option compared to gas, diesel, or coal.  Not all fossil fuels are equal.  So let’s use our real world information to avoid confusion with some mythical land filled only with big diesel generators.

There’s also the question of what efficiency we are using.  We want an apples to apples comparison so we need to be consistent with what’s included.  The total efficiency metric for vehicles is called “Well to Wheel” efficiency; it includes the efficiency from fuel extraction and transport, the engine, and finally the powertrain to the wheels.

Table: Vehicle Efficiency Comparison2vehicle-efficiency-comparisons

From the table we see that even with the current grid mix electric vehicle efficiency is double that of diesel and three times that of gasoline.  Efficiency is important but it’s not the same thing as ‘environmentally friendly’.  An engine that’s 100% efficient but runs on whale oil isn’t very friendly, at least not to whales.  The next section looks at the carbon intensity of the fuel sources.


4. Electric vehicles will reduce emissions -> by a lot in most cases

There seems to be a large amount of distrust for this, as if electric cars are some sort of scam to hoodwink unsuspecting millennials.  Let’s clear that up because it’s a big driver for EVs (pun there if you missed it).

  • The Union of Concerned Scientists did a full lifecycle emissions review3  and found the equivalent EV MPG in the US was about double that of combustion vehicles.
  • In Ontario my own analysis identified a 94% reduction in CO2 equivalent emissions from driving a Tesla Model S 85D compared to driving my gasoline powered VW Golf.  I also looked at the extra emissions from manufacturing the battery, which would be ‘paid back’ through driving emissions reductions by around 20,000 km.  Coincidentally that’s a Canadian’s average driving distance per year.  I’ve assumed 25% of the carbon is avoided/recaptured if the battery is recycled, in which case the payback occurs at ~15,000 km.


Similarly, comparisons for the four most populated provinces in Canada, the Canadian average, and the US average all show significant reductions in the table below.



5. Transport emissions are a big part of our national emissions

Some people have said that transport emissions aren’t significant and that they are only 12% of Canada’s greenhouse gas emissions.  That’s false but I think I know how they got there.  Environment Canada data shows transportation emissions are 23% of Canada’s total and roughly half of that is attributed to passenger vehicles.  That math works out to 12%, but that’s not the whole story.

That number excludes buses and freight truck transport, which would also see electrification or something equivalent.  With that included the total rises to ~20% of Canada’s total national greenhouse gas emissions.

But even that is not the whole story.  It leaves out how we got the fuel in the first place.

The oil and gas sector accounts for 26% of our total national emissions.  If we break out the emissions related to the oil processing for passenger vehicles, buses and freight trucks (i.e. the extraction, production, refining into gasoline or diesel, and transport of the fuel) the result is another 10%.

Adding the 20% for vehicles to the 10% for the oil and gas extraction brings us to a total of 30% of Canada’s total C02e emissions attributed solely to passenger vehicles, buses, and freight trucks.

Thirty Percent!  That’s a big deal.


6. Incentives will help make EVs more affordable for everyone, speeding up their adoption across the world

The purpose of incentives is to help a technology mature more quickly and as a result become economically viable for a much broader sector of the public.  Thus the benefits can be had for many more people much sooner than would otherwise be possible.   Governments also invest in the new technologies development through things like tax rebates or grants.  Incentives are one of the most democratic ways of advancing a technology; if people don’t want EVs, no government money goes to it.  If more electric vehicles can help balance our electricity demand between day and night then so much the better.

To decry the incentives on EVs while giving a pass to traditional automakers receiving hundreds of millions in factory rebates or conveniently forgetting the automotive industry bailout is cherry picking facts.


7. Right now there is no better option

I think it’s fair to say Dieselgate proved that clean diesel wasn’t what we thought.  There are also some people who say that hydrogen fuel cells are the future of transport and others say they always will be.   But EVs are here now and looking better every day.

To date the breakthroughs have been incremental, but they are compounding rapidly.  As EVs continue to grow in market share costs will continue to fall.  As power density improves the cars will go farther.  As DC charging expands and batteries charge faster, range anxiety will disappear.  As renewable energy continues to grow, total efficiency improves and electric vehicles will be even cleaner.  We are on the cusp of a paradigm shift in our transportation and energy sectors.  A shift that will help us reduce the effects of climate change, improve our air quality, and preserve our wonderful planet for future generations.

Oh and they cost a lot less to operate too.








Notes and Reference Materials:

Originally this was just a letter to respond to a newspaper article but I was able to rework  it for this blog.  I spent more than just a few nights researching, using multiple sources to justify my assumptions and calculations.  I’ve made my best effort to present the data and  offer a realistic view of the environmental benefits.  I hope you’ve found it useful.


1 RoHS –

2 Vehicle Efficiency Comparison:

Vehicle Efficiency Calculation Notes

  • The results for combustion engines are taken from a 2010 MIT study.
  • “Tank to Wheel” efficiency for electric vehicle efficiency includes battery charge/discharge efficiency (~88%), motor (~93%), inverter (95%), and drivetrain transmission efficiency (~95%).
  • “Well to Wheel” efficiencies include the efficiency in producing the fuel. For electric vehicles we’ve used the grid electricity as the fuel, in Canada that has an efficiency of ~74% and in Ontario ~54%, with around 5% distribution losses.  Ontario is lower because nuclear reactors thermal efficiency of 33% (according to the US EIA, which also shows natural gas stations are 44% efficient).  To account for the extraction energy from the fuel I’ve reduced the EV efficiency by two percent.
  • Fuel cell vehicles suffer from an inefficient production of hydrogen, with nearly all coming from steam reformation of methane, and inefficient hydrogen to electricity conversion.

Vehicle Efficiency References

3 Union of Concerned Scientists Review

4 Battery CO2e:


5 Electricity Production Mix


6 Distribution Losses


7 Electricity CO2e/kWh


8 Battery Recycling


9 Carbon emissions from combustion vehicles


Data Analysis For Facility Planning – TGH Chillers

Data is critical to facility planning.  With data organizations can plan for the long term, they can make decisions based on facts, and they can weigh options against one another.  I would say there are three criteria for useful data: availability, reliability, and clarity.  All three are necessary; if you have data but can’t access it then it’s not useful; if you have unreliable data then it’s not useful; and if you have reliable data but it’s a convoluted mess then it will be very difficult to discern anything meaningful (i.e. not useful). Continue reading

AC Motors, VFDs, and Energy Savings at Toronto General Hospital

I’d like to share two recent energy projects at Toronto General Hospital, which used VFDs to achieve significant energy savings and improve control.  When I say significant I mean that the savings could buy a house, well maybe not a house in Toronto.  There is also a fairly technical explanations of motors and variable frequency drives but I’ll leave that to the end for obvious reasons.


VFDs and Harmonic Filters on Secondary Chilled Water Pumps at TGH


Project 1: Reinstate VFD operations on Air Handling Units

At TGH we had 17 old Continue reading

Little Choices for Little Futures

Being a new Dad has given me a lot to think about, but you probably already knew that. Like in this picture perhaps. I used to just put on a jacket and go outside, now….. I make a hundred decisions before I go out the door. “Stroller or carrier? Is she warm enough, can she breathe, is she still breathing, do we have the diaper bag, are there actually diapers in the diaper bag, how long will we be gone, wait where are we going?”.  Those are my immediate concerns, but what about the future?  What about long term?

What about in 30 years when my daughter is my age?  (insert nervous gulp here)

Kara Month 2 - 7

Will we be Continue reading

The Baby Product Environmental Conundrum

Being from the Energy & Environment group at UHN, you could guess that I’m an environmentally minded person. I try to limit my environmental impact wherever possible, I also eat healthy(ish), select organic produce (especially for the ‘dirty dozen’), and avoid processed foods, I exercise, select green certified products, and limit my chemical use/exposure.  I’m an engineer, a former green building consultant, and current energy manager, so I like to research and I’m fairly familiar with these issues.  Many months ago I learned I was adding something to my resume, the title of “Father” :).


Soon after the initial joy and excitement, my wife and I realized we needed Continue reading

Electricity Peaking – Timing Matters!

It was a hot week this week, very hot and that means expensive electricity. When demand goes up the grid has to ramp up production on smaller less efficient generator stations or buy power from other provinces/states.

Ontario Electricity Demand Friday July 31 at 11:00


– From – or search for the app to see how much Electricity Ontario is using right now!


For large utility customers it’s a big issue, as their demand charges are based on Continue reading