Scientific Scribbles

The voice of UniMelb Science Communication students

Are Electric Cars Greener? Let’s crunch the numbers.

You may have heard the claim ‘EVs are responsible for higher lifetime emissions due to their large production footprint’. This myth was based off the fact that EV batteries are extremely carbon intensive to produce. Once you crunch the emission numbers for production and driving, a very different story emerges.

To account for full lifecycle emissions of a car, you need to look at:

  • Production emissions (all carbon emissions associated with the mining of materials and production of the car)
  • Driving emissions (the associated carbon emissions from the fuel type: petrol or electricity)
  • End-of-life emissions (all carbon emissions associated with recycling and disposing of the car)

End-of-life emissions for both electric and internal combustion engine (ICE) vehicles are similar in size and very low compared to usage and production emissions [1]. We will only be looking at the differences in EV and ICE production and driving emissions.

Production emissions

Due to the diversity of car types and sizes, there are a range of estimates for the production emissions of cars. Low estimates start at 2 metric tonnes of CO2 [2] per car, with the highest estimate at about 17 metric tonnes [3]. Excluding their batteries for a moment, EVs have a slightly lower production carbon footprint than ICE cars. This is due to their simplified and more efficient design. In this comparison, we will assume an average production footprint of 12 tonnes for ICE cars and 10 tonnes for EVs plus their battery.

EV batteries account for 15-70% more production emissions depending on how large the battery is [4]. In this comparison, we will compare a standard EV battery (30kWh) and a long-range EV battery (100kWh). The standard battery produces an extra 3 tonnes while the long-range battery produces an extra 10 tonnes of production emissions [5]. Adding the car and battery production emissions, EVs do in fact incur a significantly greater carbon footprint compared to ICE cars. How will the driving emissions compare?

Driving emissions

Exhaust emissions of ICE cars contribute to the vast majority of a car’s carbon footprint. But how long will it take for an ICE car to offset its lower production emissions? There’s a simple way to calculate this!

By adding the production and annual driving emissions by time (T) for ICE cars, and comparing it to the production and annual driving emissions by T for EVs, you can solve for T to find the number of years it takes for ICE cars to produce greater overall emissions.

To make it harder for EVs, we will give ICE cars the benefit of the doubt and assume that the EVs are charged on a grid powered entirely by natural gas (ignoring the 20% and increasing contribution of carbon free electricity) [6]. For the 30kWh EV, this gives us an equation of:

Solving for T gives us 0.94 years. This means the standard-range EV will compensate for its production emissions within a single year! If the car’s battery ever needs to be replaced, the emissions of the second battery are offset within an extra 3 months. Considering the average car lasts 10-20 years, these upfront emissions are more than paid off over its lifetime. It is a similar story for the long-range EV, which takes 2.5 years to break even with ICE cars (or 5.5 years with a battery replacement).

Lifetime emissions

The full impact that EVs have on reducing emissions can be better shown when comparing a full lifetime’s worth of emissions. We will assume an average lifespan of 20 years for each car. To give ICE cars the benefit of the doubt, we will not factor in maintenance such as engine replacements and the EVs will have a battery replacement. Crunching these numbers results in the standard EV producing less than 50% and the long-range EV producing only 60% of the lifetime emissions of an average ICE car. This result is confirmed by the studies listed below. These numbers become more and more favourable when you consider the increasing contribution of clean energy supplying our energy grid.

Of course, some regions are powered predominantly by coal, resulting in EVs breaking even in lifetime emissions. However, they still have the benefit of removing pollution from urban centres and confining it to the power plants where emissions scrubbing technology can be installed. Rest assured, if you’re in the market for a new car, buying an electric vehicle will likely be cheaper, more convenient, and a whole lot better for the environment.


Further reading

[1] Environmental life cycle assessment of cars, 2012, Yale University.

[2] Life cycle analysis of new cars, 2000, MIT.

[3] Back-of-the-envelope calculation of a carbon footprints of cars, 2010, The Guardian.

[4] Cleaner cars from cradle to grave, 2015, Union for Concerned Scientists.

[5] Life cycle energy consumption and emissions from li-ion batteries, 2017, Swedish Environment institute.

[6] Australian emissions by sector, 2018.

Why the time on your phone is always accurate?

Pocket watch and wrist watch were commonly used in the past. However, they are not very convenient that the user have to adjust their watch frequently by listening to the radio. Now, people don’t have to adjust their watch for two reasons. For one thing, the watch is much better than before and, for another, people tend to check the time on their phone instead of watch, because our phone can adjust the time themselves.

Who tells them the exact time? Why is that time reliable?

Fig1. If ture this on, the time in your phone will be automatically adjusted. Screenshoot from the author’s phone.

At first, time was defined from the period of a day. But, since the orbital of the Earth is not a perfect circle, the duration of each day are different from each other. We can average the length of each day and get Mean Solar Day, which is equal to 24h-00min-00sec. This time observed, recorded and reported by Royal Greenwich Observatory in London.

Fig2 The length of each day in a year are different. Drawn by author.

This time system seems reliable but it require a lot of work on observation, thus, the clock is hard to adjust. What’s worse, the Earth rotation is getting slower and slower. People need a new time definition based on a fixed period on Earth.

In the early of 1900s, people found that if a piece of Quartz (crystal) as put under alternating current, it will vibrate in a fixed frequency. The Quartz clock was invented at 1927, and noon after that, time was newly defined by the vibration frequency of the Quartz. The Quartz clock was so accurate that the uncertainty is only 0.001s/day.

However, the new definition is also not reliable because the vibration frequency is highly dependent on temperature, quality of alternating current, shape, size and orientation of that small piece of quartz.

In 1967, new time definition was published that’ the duration of 9192631770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium-133 atom’. In short, this new definition is based on the light frequency which can be absorbed by a group of atom. The absorption is the nature of an element, which can never be affected by other factors. This time is called International Atomic Time (IAT), started from midnight January 1st 1958. The time used before was Universal Time (UT).

Because the rotation of the earth is getting slower, UT always goes more slowly than IAT. Which one we should use? UT is more related to real life while the IAT is more accurate. The answer is neither. Why not use a time system which van satisfy these two aspect?

Coordinated Universal Tome (CUT) was introduced. The interval of every second is fixed, equal to the IAT.

If the CUT goes so far away from the UT which is about 1 second, as shown in the picture. One more second should be added to the CUT to wait for the UT. Thus, the CUT always match the sunrise and sunset.

From 1958 on, up to 37 seconds have been added to the CUT.

Many countries take the responsibility to calculate the difference between the atomic time and the Universal Time and these result will be reported to the Bureau International des poids et mesures in Paris, France, on the first day of every month. They will calculate the CUT and make sure the difference is less than 100ns. Then, the result will be reported to every country and delivered to every digital device user via the Internet.

Psychedelic drugs: the key to mastering mental illness?

Before he left us on this earth, Steve Jobs – the biggest technological mogul of our time – gave credit to the psychedelic drug LSD for allowing him to open his mind and view the world from a different perspective. He once stated that “taking LSD was a profound experience” which he claimed was the “most important experience” of his life.

But when I hear the words ‘psychedelic drugs’, I think terms like ‘bad news’, ‘loss of control’ and ‘60s dance party’. There is a lot of stigma surround this class of drugs and their impact on society in the last 60 years, and a lot of this probably stems from the fact that they are illegal substances. They include drugs such as LSD, MDMA and Magic Mushrooms, all of which are highly illicit and are often associated with dangerous behaviour, and bad experiences, or ‘trips’, leading to mental health issues.

What exactly are psychedelic drugs?

Psychedelic drugs, as their name suggests, are powerful hallucinogens that induce a mind-altering state of distorted reality and consciousness. People who trip on psychedelic drugs often see and hear things that aren’t actually present, but which feel exquisitely real, and experience deep changes within their thoughts. The actual term ‘psychedelic’ comes from the Greek words ‘psyche’ (mind) and ‘delos’ (to manifest), which essentially describes a ‘manifestation of the mind’.

Interpretation of a Psychedelic experience. Image by Marcello via Flickr. (CC BY-NC-ND 2.0)

However, these drugs were not always outlawed, and lots of research was poured into their potential as therapeutics for various mental health disorders in the decades leading up to the 1960s. But this was quickly snuffed out in the late 60s when laws passed deeming it illegal to interact with these drugs.

Yet research has recently sparked up again, leading towards a movement to make psychedelic drugs legal and using them in conjunction with counselling, in order to create a new practice called ‘psychedelic therapy’. The extreme effects on sensory perception that these drugs cause may actually help the patient to break down their barriers faster and access a level of consciousness not normally available to them in everyday life, leading to profound therapeutic breakthroughs.

The psychedelic agents of interest

LSD is a synthetic chemical that acts as a serotonin receptor stimulator, which has been shown in clinical trials to be particularly useful in treating anxiety. This was seen in a study of patients with life-threatening diseases, and intense anxiety because of this fact. These participants all reported a significant decrease in anxiety and increase in quality of life following guided therapy sessions under the influence of LSD. LSD has also been linked to the promotion of neuroplasticity – that is, LSD is able to increase cellular mechanisms that lead to a change in neuronal connections in the brain, such as making new pathways.

MDMA, another synthetic psychedelic drug, has recently been employed in studies to treat people with post-traumatic stress disorder (PTSD). PTSD is a particularly difficult disorder to treat as the current options are limited and often not well tolerated in patients. However, treatment of micro doses of pure MDMA alongside psychotherapy for these individuals was found to be particularly effective at treating their PTSD.

The active ingredient in Magic Mushrooms, known as psilocybin, has also been proposed for the treatment of severe depression. In particular, it was used to treat depression in patients with terminal cancer, and it was found to cause immediate positive effects, following only a single dose therapy session.



Synaptic connections in a normal brain, vs. connections in a brain on psilocybin. Image by Steve Jurvetson, via Flickr. (CC BY-NC-ND 2.0 )

The use of these psychedelic drugs may provide a somewhat fast-tracked pathway to treating severe mental illnesses, as they allow patients to see, as Steve Jobs once put it, that “there’s another side to the coin” – they may be able to use their subconscious to break past the issues that they might not be able to during normal therapy sessions.

Yes, illegal drugs are illegal for a reason – but why are so many other illicit drugs used as treatments for various conditions, when psychedelic drugs are taboo? Methamphetamines can be prescribed for attention deficit disorder, and opioids are frequently used as analgesics – both classes of drugs have extreme associations with addiction and overdoses. While psychedelics have a bad reputation – and don’t get me wrong, they can be associated with anxiety attacks and dangerous behaviour when used in uncontrolled settings and alongside other illicit substances – they are actually not drugs of addiction or used as part of compulsive drug habits.

The danger of illicit drugs is the totally uncontrolled nature of their manufacturing, distribution and use; they are treated negatively, so they become the poster child for bad publicity.

Opening our minds to psychedelic therapy

Using these compounds in micro doses, in their pure forms, in the presence of trained medical professionals, these drugs hold incredible potential to help people who really need it, and the benefits probably outweigh the risks. One illegal drug in particular has been the centre of controversy regarding its potential for pain management and treatment for a variety of diseases including fibromyalgia, Parkinson’s disease and cancer. This drug, which was recently accepted for use in Australia in 2018, is marijuana. If more clinical trials could take place to further prove the effectiveness of psychedelic drugs for their various diseases, we might just see them follow in the footsteps of medicinal marijuana and return to society as legal substances.


Maldives and climate change

In recent years, it has become almost axiomatic to argue that global environmental change and sustainability science are intertwined, as changes in the biosphere can alter any function and its structure and have momentous effects on the planet. Several different nations with emerging economies such as Brazil, China and India has acknowledged that climate change has become an important issue for this century, As global surface temperature has an increase of 0.6 degrees per year and is this reasoning is linked with anthropogenic activities over the past two centuries, research has shown that this is the hottest decade on record since 1990. As global sea levels have risen dramatically throughout the year, this produces a chain effect in the globe as gradual shrinking of glaciers are thawing in permafrost regions and this places huge threats in human settlements as this increases the chances of flooding. With thousands if not millions of people living on the low lying they are in particular prone to these climate catastrophes and this also led to a so called development of environmental refugeeism. Those who are forced to leave their traditional settlements, temporarily, or permanently due to climate or environmental disruptions are environmental refugees as this jeopardizes their existence with their overall quality of life. Climate change is going to affect the republic of the maldives as it is situated in a low elevation land area with majority of the land mass being placed less than 1 meter above sea level. This pose them in terms of extreme range in terms of vulnerability to climate change.  As climate change is known to affect the front face shorelines of the maldives in the future, it can affect the Maldives overall economy in particular fishery and tourism which is a major source of income for the Maldives economy. If conditions continue to deteriorate because the Maldives can begin a sustainable development plan through environmental risk assessments. In order to adapt in the upcoming decade or two to climate change due to the loss of corals which also causes the loss of habitat for fish meaning Maldives could force their citizens to have less fish as part of their diet, in order to support the demand of food means the possibility of outsourcing and increase the input food from overseas to which will drive up the food prices. As food is a necessity for all, the citizens of Maldives might cause conflict and migrate to other places where they can afford to purchase food in order to survive as a form of survival strategy.

A Reflection on Communicating Science from a Self-Proclaimed ‘non-scientist’

While containing the word science, the ‘social sciences’ are about as far as you can get from tour traditional ‘hard’ sciences like organic chemistry and quantum physics. Coming from a Bachelor of Screen Studies into a Masters of Geography, I’ve had to spend quite a bit of time playing ‘catch-up’ with some of the core principals of science such as maths, statistics and data analysis, seeing as my previous venture into academic life consisted of analysing how cinematography and colour palettes in films are used to portray deep philosophical concepts subconsciously to their audiences. Initially, I believed my expansive knowledge on this subject would be rendered quite useless, particularly when it comes to tasks like these where we are asked to communicate ‘science’ through our blogs and reflect on our knowledge and interests. However, I’m starting to understand that much like how the ‘hard’ sciences can be seen and reflected on in everyday life to explain the intricate workings of the world, the ‘soft’ sciences play just as valuable a role.

One of the hardest tasks of my semester has been trying to figure out what to talk about in these blogs. I figured that anyone can go on google and write an informative piece about a specific ‘science’ topic, but I wanted to see what I could uniquely bring to the table as a ‘non-scientist’ venturing into the science world throughout my studies and potentially provide some insight for other people who might be struggling like me. So, here are some things that I’ve learned through this semester as I’ve learned to communicate my own brand of ‘science’.

Stick with what you’ve got

As I mentioned before, anyone can google ‘physics 101’ and write a (no doubt fantastic) piece on what they learned, but as a social scientist you get to bring something unique to the table, so go with it! Chances are if you did an undergraduate degree in the arts then you’ve definitely had the opportunity to study some of the weirder things in life. Whether that’s carrier pigeons, the history of pirates or the impact of memes on the current generation – you’ve definitely got a unique knowledge set up your sleeve and don’t be afraid to use it. Although your knowledge might not meet the conventional definition of ‘science’, have a think about the practical applications of theory and how you can observe what you’ve studied in everyday life.

Be engaging – so engaging you even hook yourself in

Whenever you can, don’t waste an opportunity to hook someone into your strange and niche little knowledge pocket. Use stories, images, songs, movement, colour – never shy away from the little voice in your head which is the sole embodiment of your inner flare for the dramatic. If I’ve learned anything from this subject (which don’t worry – I’ve learned a lot), it’s that the limit doesn’t exist. Don’t be afraid to push the boundaries, you won’t get many other opportunities to do so at University. Sometimes even you know that what you’re trying to communicate is boring, so that’s where you have to put yourself in someone’s shoes and figure out what the best way for them to receive this information would be, and sometimes (just sometimes), that’s interpretive dance.

Don’t be afraid to reflect

If you’re a social scientist, you’ve been blessed with something that no other scientist in the world gets to have, and that’s an opinion. As a social scientist, you’re allowed to have opinions on the interpretation of theory and be critical of what you’re learning, for the hard sciences it’s a little more difficult to have an opinion of the number of chromosomes found in the average human cell or what the square root of 4 is. This is not to say that hard scientists don’t have opinions or that science can’t be controversial, but there’s a lot more flexibility in the social sciences where the majority of what you learn is just a theory that’s open for interpretationThis means that by now, you should be used to weighing in on things and putting your own twist on whatever you learn so don’t be afraid to use that to your advantage. What is your opinion on the square root of 4? Unsure? Then do some research and write a creative piece on it (spoilers: it’s 2). In fact, while we’re on the subject of the number 2, you could write an interesting piece about twins, or dual citizenship laws around the world, or even chopsticks. The moral of the story is, science is everywhere and it’s a part of everything – don’t be afraid to explore it!

This subject has played a key role in my journey into the science world and the community within it. I’ve had the opportunity to explore realms of science I didn’t even realise existed and I’ve been pushed out of my comfort zone (in a good way) to see all the different methods of communication you can use to get a single message across. I’ve thoroughly enjoyed using these blogs as a space for reflection on the wider world of science and as a means of also seeing what my peers are learning about every day at university and in life.

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