If you didn’t catch the previous parts of this series on what electronic tests are and how they relate to sustainability, you can find the first part here! (No really, otherwise you’ll be very confused if you read this article otherwise 😁).
To briefly summarise: improved technology is the key to sustainability–from energy-efficient LEDs to environmentally-friendly batteries! But many tests are needed to improve technology and they look for complicated ‘failure modes’ (the events that lead to electronics breaking).
Given all these unique types of tests, why did I claim up above that ‘EVERY’ electronic has slow testing? Well, ‘EVERY’ electronic from tiny batteries to giant power cables has two important (but slow) types of tests: accelerated lifetime testing and burn-in testing. As I explained in the first article, these tests are often done by manipulating the exact same variables: temperature, humidity, current, and/or voltage higher and performance over time.
To make it less theoretical, I’ll talk about lifetime testing.
Let’s say you’re a brilliant, laser in a LiDAR sensors that many automated electric vehicles rely on to enable cleaner transportation. You are about to be tested to see if you work! You will be subjected to a 75°C temperature (with all your other laser friends) and see how long it takes you to break. Here’s what I’d see:
This is a curve like many others in electronics testing. It shows how variable X increases and/or decreases as the time variable increases and a device ages. Basically, as you shine longer, you age more and get tired. You need more ‘fuel’ (i.e., current) to keep you going. Eventually, you’ll need so much ‘fuel’ that you just won’t meet the user’s laser shining needs (and these needs can be important to the user, and can be detrimental from an environmental, economic and social perspective)! Even though, from a technical perspective, you may still be functional you may not offer the desired qualities to the end-user.
Different lasers, have different performance. As shown in Figure 1 lasers indicated with a maroon, purple, and pink colours have a 1000+ hours performance, and it is uncertain as to how long it’ll take for their fuel needs to increase considerably. The Arrhenius equation is often used to figure out what the laser lifetime would be at regular temperatures, given what we know about their lifetime at high temperatures. Warning… CHEMISTRY ahead. Do you remember this monstrosity from high school???
This is the Arrhenius Equation, and if you haven’t seen it since your high school chemistry class, fear not! Here’s the oversimplified version:
- k is how fast atoms move.
- T is the temperature.
- k is equal to a complicated mess that we don’t care about. We just need to know k (how fast atoms move) increases as T (temperature) increases.
This allows us to model how fast atoms move at different temperatures (among other things). And remember what I said in the second article in this series: The faster atoms move the faster electronics degrade. So, the Arrhenius equation can be used to model how long it will take for electronics to degrade at different temperatures: Life is inversely proportional to how fast atoms move (how naughty, and chaotic their life can become), which is complicated to calculate.
In fact, this is exactly why we go to such great lengths to add heat sinks or cooling systems to devices. Cool right? Based on chemistry, and a gallop of physics and math we can model how sustainable technologies like, electric vehicles, solar panels, wind mills, would last while being subjected to environmental conditions (e.g. radiation, heat, humidity and wind) for many years.
Now, what does laser Figure 1 tell us about lasers’ performance before the 100 hours pass? That’s where the burn-in testing happens (e.g. every laser is run for 100 hours to find any defects). The issue is that many failure modes for electronics happen ONLY in that first little while of testing (it’s like you only get chickenpox once— usually when you’re young). But for lasers, it’s more like the atoms in the crystal structure ‘dislocate/diffuse’ to the wrong places when they’re young. The problem with that is that it’s pretty hard to predict all those specific one-time failure modes. Burn-in testing is hard to extrapolate which makes it even harder to prevent potential lower quality electronics to be placed on the market.
EVERY product needs lifetime testing and EVERY unit of every product needs burn-in testing for sustainable electronics and electrical equipment to be placed on the market. Even though, there are considerable ‘costs’ (e.g. energy, carbon emissions, operational and maintenance costs) involved in testing millions of electronic and electrical equipment made at factory, these could be significantly lower than the ‘costs’ associated with electronics and electrical equipment that becomes easily obsolete, especially considering the fact that these become waste very quickly and are alarmingly mismanaged. An in-depth system-based sustainability assessment is needed to demonstrate the impacts involved!
By this point in the series, I hope you realise how important technology innovation and testing is for achieving sustainability in the long-term. With this in mind, I’ll finally wrap up the next (and last) part of this series by looking at solutions to all the major problems I’ve highlighted so far! 🛠️💪