The electrification of mobility

The world is full. Humankind is using 1.5 times Earth's capacity.

This is according to Cavan Hill, GM for Sasol New Energy, speaking last week at Popular Mechanics' FutureTech event.

A lot of energy is wasted, according to Hill. "In fact, more energy is wasted than what we actually get efficient use out of. Some of it is our fault; some of it is just because it's easier to leave things on; some of it is purely because of the laws of physics. For example, an incandescent bulb gets hot; that energy is not useful for the service we get, which is light; it's wasted."

There is no such thing as an electricity mine or well, continued Hill. "We make electricity from other forms of energy. Electricity is a very useful form of energy, but we can't go find it. We have to take other forms of energy and turn it into electricity, and the big problem with electricity is that we can't store it effectively. We take electricity and convert it into some other form of energy [and store it that way]."

Referring to the current energy situation, Hill said the simplest way to describe it is that "the world is full".

"When comparing humankind's demand on the Earth with Earth's regenerative capacity, humankind is using more of the Earth's capacity than the Earth has capacity to regenerate at the moment."

He used the analogy of a bank overdraft. If an accountholder withdraws more money than what goes into the account, he will initially be able to tap into the overdraft. Eventually, however, that overdraft will run out and that's when problems arise.

Going forward, the impact of carbon and the energy system is going to change, said Hill.

There is quite a good mix of energy sources and services, said Hill. "When it comes to transportation, it's basically powered by petroleum, by crude oil. The reason for this is that crude oil is a nice compact form of energy. Petroleum is a pretty efficient way for driving transportation, but it's also very inefficient."

Regarding future energy, Hill outlined a number of likely and unlikely transportation scenarios.

Unlikely developments are nuclear-powered cars and quantum teleportation, Hill noted.

What is likely, said Hill, is that the system is going to become more efficient and there will be less energy wastage. He pointed out that this is already happening, as one can note when comparing the fuel consumption of cars today with cars of 20 years ago.

"Part of it is driven by better technology, part by simple economics," said Hill. "There's going to be a lot of government policy changes, the aim of which is to change transport. In order to reduce the demand on the system, changes will be driven by policies."

Another change that is required is that of human behaviour, said Hill. This could be done through, for example, taxation changes. "Unfortunately, e-tolls are just the beginning. One of the aims of e-tolls is to start changing behaviour."

The technology for the electrification of mobility exists, said Hill, it's just not cost competitive yet. That will change, however, and batteries are key.

"The problem is that the cost of the battery and the capacity of the battery are limiting large-scale adoption of electric vehicles. But that can change." If you look across adoption, Hill noted, lead acid batteries are the primary drivers of electric vehicles, but these are heavy and provide about 40 watt hours per kilogram. For example, he noted, lithium ion batteries deliver about 160 watt hours per kilogram, adding that while these batteries are expensive, the chemistry is improving.

An electric motor, noted Hill, is over 90% efficient. "So once you have electricity in a vehicle and you convert that into motion, it's very clean and very efficient. The problem is to store enough in the battery to get sufficient range."

He noted that chemistries are being developed, such as zinc and lithium sulphur, which will improve the energy stored in batteries, adding that Sasol New Energy is making strategic investments in this area.

Batteries are no different to any other technology - as technologies improve, the cost comes down. As either battery costs decrease or fuel prices increase, plug-in hybrid vehicles will become more competitive, he notes. And ultimately, those costs will come down even more and pure battery electric vehicles will become competitive (depending on electricity prices).

However, he pointed out, this comes back to the problem of storing electricity. "What's going to happen in future is, as we move more and more towards electricity, the grid - the system that moves electricity around - has to become smarter, which we call smart grid. We're going to have generation from renewables; we're going to have time-of-day prices for electricity. At the moment, it makes no difference whether you plug in your hairdryer at 5pm or 2am.

"Eskom sends out alerts asking you to turn off your pool pump, etc, between 5pm and 8pm. You do it because it's the right thing to do, but there's no economic incentive to do it, and that's because there's no price signal to change behaviour. That will change."

He referred to practice in Europe where, on "lazy Sunday afternoons when the sun is shining on the solar farm and the wind is blowing on the wind farm", there becomes a surplus supply of energy, leading to electricity prices becoming negative, purely because there is nowhere to store it.

In order to enable this, the system needs to change to accommodate smart charging, Hill noted, adding that the electricity system spreads much further than the petrol station network.

What could materialise in the future is that, instead of getting the first hour of parking free, shoppers who drive electric vehicles could get their first hour of battery charging free in the parking lot as an incentive to shop at a particular mall.

"So it's not just technology change that's needed; the system needs to change too. And that's going to change the whole way we look at mobility," said Hill.

He took this further, saying once there is an ability to start connecting the electric storage in vehicles, we can start enabling the smart grid. This will allow users to start shifting energy around. He provided the example of an electric car that has 100km left on the battery, but the owner only needs to travel 5km. That extra energy can be used to power the user's house lights or can be sold back to the grid.

He noted too that electric vehicles running on renewable energy are cheaper to operate because the maintenance on the cars is much lower and there is potential for the cars to last much longer. Also, the cost escalation on renewable energy is low, as the price of the sun and wind won't change.

Technology changes, economics change, and increased electrification will completely change the concept of mobility, Hill concluded.