“Exponential” is one of those great words loved by the start-up community and technology investors alike. Exponential technology growth curves allow you to hide any number of early mistakes while also reaching massive audiences quickly. Exponential solutions can be the answer some of our biggest medical, health, energy and information challenges, even solving problems we didn’t know we had!
Exponentials are exciting. Whether it is transistors on a chip or users across the globe, they expand in a dramatic power curve.
But exponentials can also have a dark side. Fake news spreads because of the exponential power of social media. By comparison, Wikipedia has become the planet’s most trusted source for facts. Although errors and lies exist on Wikipedia, it hasn’t served as an effective platform to spread these falsehoods. The difference between Wikipedia and its social media counterparts is that it is linear rather than exponential.
Post a fake fact to Wikipedia and it might stick for a while, but the only people who see it are those that specifically visit the page. There is no propagation or viral sharing, making the platform much less attractive to spread controversy. Wikipedia is perhaps best described as a linear technology.
Like exponentials, linear solutions also grow in capability and reach, but only at an incremental pace.
Despite the downsides, the power of exponentials has been crucial for humanity. It wasn’t that long ago that starvation was the human norm. Populations regularly ran out of food and there were credible predictions that our era would be one where population growth would cause mass famine.
Exponential approaches to agriculture changed the game. Major crops, such as wheat, barley, and corn, have seen yields increase by a factor of five to ten over the past century. When combined with land use changes, food production technologies have been genuinely exponential.
Just as we would be seeing mass starvation today without exponential approaches to food production, so we will have a massive environmental crisis later this century if we can’t find exponential solutions to reduce and remove carbon and other pollutants from our everyday activities.
Charts showing what it would take to be a zero-carbon society by the middle of the twenty-first century make it clear that we’re kidding ourselves if we think linear reductions in our environmental footprint are going to be enough.
In energy production, we have some great linear technologies available to us which can grow their impact: predominantly solar and wind. Even combined with battery storage technology, most curves indicate incremental improvement and reach.
It is particularly in transport that we see the limitations of linear approaches. Many things can store energy, but what has made oil so attractive is its high energy to weight ratio which is still two orders of magnitude greater in density than the best batteries. This wouldn’t be an issue if battery technology was exponential and following something like Moore’s Law, but it isn’t.
The car makers are battling this out at the front line with one group, largely led out of the US, pushing for battery powered electric cars. The other, largely led out of Japan, are arguing for a hydrogen economy.
The debate matters because transport requires infrastructure. If there aren’t points to refuel or recharge available, people won’t take-up either technology. It’s unlikely that any country can leave it to the market to get to scale in time, meaning we need to decide as a society on the technology to back and scale the supporting infrastructure.
There are arguments in favour and against both batteries and hydrogen, but it is important the discussion is framed in terms of the linear versus exponential nature of the technologies. Where battery technology is inherently linear in its improving efficiency, hydrogen starts with an energy density that is roughly triple that of oil. While extraction of that energy is inefficient, its improvement more closely matches that of the exponentials we are familiar with.
The power of exponentials can be easily squandered. Whether is our low digital productivity benefit on the back of digital disruption (see Where is the digital-fuelled growth), or some of the food quality and health challenges we face after a century of the agricultural revolution, we need to make sure we understand the trade-offs. Anyone who relied on their iPhone alarm to wake-up in 2010 understands this after they slept through on the first day after daylight savings. Because the iPhone was exponential, the reach of the glitch was massive.
Understanding the trade-offs of exponential and linear solutions matters as we can only navigate our century’s greatest challenges if we find the right answers quickly.