There is an amazing, almost magical efficiency to electricity when it is applied to real-world tasks – and it can meet the energy demands of the future without sacrificing standards of living and innovation.
RE-INVENTING OUR energy supply is one of the biggest challenges of our time. What advice can an electrical engineer offer to meet this challenge?
Accompany me on a journey into three possible energy futures.
The first is one where we continue much as we are today, business as usual. We burn coal to generate most of our electricity and use petrol to run most of our vehicles.
The second energy future is often referred to as the hydrogen economy – we transform our society to use hydrogen to store energy, run our vehicles and heat our homes and factories.
The third energy future is one where electricity is king. A world where electricity takes on a vastly increased role to supply nearly all of our energy needs, contributing much more broadly than it does today. I’m going to refer to our world under this third scenario as the Electric Planet.
Burning fossil fuels has the advantage that the cheap energy it produces underpins the strength of our economy. The downside is that burning fossil fuels also generates massive amounts of carbon dioxide. I don’t know why, but for some reason the figure of 283 parts per million as the historical atmospheric concentration of carbon dioxide was burned into my brain while I was still at school. Last week, we passed 400 parts per million, a symbolic milestone. At 40% above the historical average, this is a level that the planet has not seen for more than a million years.
We need an alternative to the world of business as usual. That’s where my other two futures come in.
LET’S BEGIN WITH the hydrogen economy. It has been much touted, and billions of dollars have been spent on research. But it has problems.
The appeal of the idea is that when you burn hydrogen the only by-product is water. Pure water. The good news is that hydrogen is all around us. The bad news is that it doesn’t exist in usable form.
The cheapest way to obtain hydrogen is from methane, better known as natural gas. However, extracting the hydrogen from methane is an energy-intensive process that generates carbon dioxide as a by-product. Which rather defeats the purpose. We would be better off if we simply burnt the methane for transport and heating in the first place, instead of converting it into hydrogen.
The cleaner way to obtain hydrogen is to use electricity to split water molecules in a process known as electrolysis. If the electricity is from a renewable source such as solar, then the process is emissions-free. Hydrogen from electrolysis sounds perfect. No carbon dioxide emissions during manufacture of the hydrogen, and no carbon dioxide emissions during combustion in a vehicle.
On this basis, many people have proposed we should use hydrogen to replace petrol for transport, and to replace fossil fuels for heating in homes and factories. The problem is that in practice there are massive inefficiencies, costs, and hazards working with hydrogen. From the electrolysis to create it, followed by compression or liquefaction to deliver it, and then hydrogen’s eventual combustion; each stage is replete with losses.
In addition, storage is hellishly difficult, because hydrogen is the most slippery element of all, oozing through the walls of metal and plastic containers. And it can be dangerous. Once out, it forms an invisible, odourless, explosive mixture. Images of the burning Hindenburg airship leap to mind.
Then there is the cost of brand new infrastructure. In Australia alone it would cost many hundreds of billions of dollars to replace the petrol and natural gas distribution systems with a hydrogen-distribution system.
Notwithstanding these problems, there was a period where the hydrogen economy was the rage. Over the past two decades, car companies such as GM, BMW, Mercedes Benz and Toyota spent billions developing prototype hydrogen cars. Despite this expenditure, you still cannot go out and purchase a hydrogen car.
Realistically, the hydrogen economy has no chance. Which sets the stage for my third scenario: the Electric Planet.
THIS VISION PLAYS out in two phases. The first phase is to replace our existing electricity supply with clean electricity. The second is to generate a lot more of it, then use the additional electricity to replace the fossil fuels that are currently used for transportation, and for industrial, commercial and residential heating.
There are already widespread discussions and plans for the first phase, but the second phase is a significant expansion of current proposals.
Let me illustrate, using averages of figures from Australia and the United States, to serve as a general example representative of developed economies.
Imagine a scenario in which we use clean technologies to generate all the electricity we currently consume. With a snap of our fingers, we would instantly wipe out 34% of our greenhouse gas emissions. The question then follows, how much more can we achieve in the second phase under an Electric Planet scenario?
Today, transport contributes 23% of greenhouse gas emissions. Nearly two-thirds of that is due to light vehicles such as cars and SUVs, while the rest is from trucks, trains, buses, ships and aeroplanes. I know from my own time working with electric cars that in a few decades we could convert all the light vehicles to electric. And we could also convert a good fraction of the buses and trains.
By converting all the light vehicles and some of the heavier vehicles to run on clean electricity we could easily remove two thirds of the transport-related emissions. That’s another 16% saving, which added to our previous 34% provides a 50% reduction in emissions. To achieve this, we would have to generate a lot more electricity than we do today, and it would have to be clean.
What next? Let’s shift our attention to industrial, commercial and residential energy consumption. These three sectors of the economy contribute 27% of greenhouse gas emissions. The majority of this comes from burning fossil fuels for heating. If we were able to generate even more clean electricity to replace these fossil fuels as well, we could remove at least two thirds of the greenhouse gas emissions in these sectors too – that’s another 20% saving.
With the previous 50% reduction, this adds up to a very substantial 70% reduction in greenhouse gas emissions.
Importantly, unlike the hydrogen economy, the Electric Planet doesn’t need us to start from scratch setting up a new production and distribution infrastructure. Our towns and cities, our industries and rail lines, and even isolated homesteads, are already connected.
Even better, the reduced emissions are achieved accompanied by ongoing technological growth and without asking society to compromise its high living standards. Furthermore, if our shift to the Electric Planet is not rushed, the transformation need not be significantly more costly than the business as usual case.
For example, coal-fired electricity generators can be closed down and replaced with clean alternatives when they reach the end of their design life, while electric cars will replace petrol cars in the ordinary course of consumers replacing their cars.
By introducing new low-emission technologies in an orderly fashion, there is scope for the economy to grow as we design, manufacture and build new equipment and distribution infrastructure.
AT THIS POINT, I know what you’re thinking: it sounds too good to be true. Indeed, it is entirely reasonable for you to question what is so wonderful about electricity that it should earn the exalted position in which I hold it. Why should electricity be king in my court?
The answer lies in the amazing, almost magical efficiency of electricity when it is applied to real-world tasks. I’ll give you two examples.
First, take a balloon-full of natural gas and use it to fuel a car. The car might run, say, one kilometre. Now take that same balloon-full of natural gas and convert it to electricity – in a modern power station, where you’ll get better than 60% efficiency. Feed the electricity to an electric car to run an electric motor. How far will the electric car run? Three kilometres! Despite the up-front losses converting the chemical energy of the natural gas into electricity, the efficiency of electric motors and lithium-ion batteries is so much better than internal combustion engines that the electric car will go three times farther. Essentially the same happens when you compare electric cars to hydrogen-powered cars. That is, the electric car drives three times farther.
If you think electricity looks good by allowing electric cars to drive three times farther, you will be astonished by the second example.
There is an existing system to heat your hot water at home called a heat-pump electric hot water service. Through a process of transfer from the atmosphere, heat-pump systems can put more heat energy into your water than the electrical energy that is used to operate them. So much more, that if we get our balloon-full of natural gas and make the same sort of comparison that we did for the car, you get 1.5 times more hot water using the electricity created by burning the natural gas, than if you burnt the natural gas to heat the water directly.
When I’ve presented these quite astonishing examples I’ve frequently been challenged: “Yes, but Alan, you’re forgetting the 80% loss of electricity between the power station and the home.” Well, that would certainly undercut my argument, if it were true.
Luckily for me, and for all of us, it’s an urban myth. The average transmission loss for electricity in Australia is just under 6%. We can easily live with that small loss.
Other critics challenge me on total lifecycle analysis, pointing out that lots of carbon dioxide is emitted during the manufacture of the lithium ion batteries required for electric cars. Yes, but those emissions will be much reduced in the Electric Planet, because the electricity used to create the batteries will be cleaner than today.
BUT I DO ADMIT to one sleight of hand. I have taken it as a given that we can get all our electricity entirely free of greenhouse gas emissions. In reality, I do not expect that we will be able to achieve zero-emissions electricity at the scale we need.
However, if we lower the bar a little, to allow electricity produced with low emissions instead of zero emissions, this can still be acceptable from an environmental perspective, and eases our job considerably.
What we are looking for is an abundant supply of low-emissions electricity that happens to be economically achievable. There are several contenders, some proven, some not.
Coal combined with carbon dioxide capture and sequestration is a contender, but it is unproven on a commercial scale, so we cannot rely on it yet. The same is true for geothermal.
The proven high-capacity sources are wind, solar, hydro, biomass, nuclear and natural gas.
Of these, the renewable sources have known limitations. Wind and solar are zero-emission but intermittent; hydro is zero-emission but faces new-construction restrictions; the various forms of biomass are either available in limited quantities or would displace food crops.
Moreover, for a variety of reasons that can be concluded from a recent draft report by the Australian Energy Market Operator, renewable sources have a higher capital cost and will potentially be less reliable if they are implemented in the absence of geothermal electricity.
If geothermal does not eventuate as a viable contributor, an alternative form of non-intermittent energy will be needed to supplement the renewables. By supplementing the renewables they become practical as large-scale sources of electricity. This will especially be the case when we try to generate the much larger supply of clean electricity that will be needed for the Electric Planet.
So, to the non-renewables. An obvious but contentious contender is nuclear electricity generation. It would provide a transformational opportunity to reach our clean electricity goals. As such, it is very important to continue the debate on nuclear electricity, but the Electric Planet dream would be under threat if it relied upon the large-scale adoption of nuclear power in Australia.
That leaves natural gas. Whether it be conventional, shale or coal seam, natural gas is, of course, a carbon-emitting fossil fuel. But it is far more acceptable than its relatives. Its older cousin, brown coal, which provides most of our electricity in Victoria, emits 1200 grams of carbon dioxide per kWh of electricity. Black coal emits two thirds that amount, while natural gas emits as little as 500 grams, just over one third as much as brown coal.
That means natural gas isn’t ideal, but at nearly three times better than brown coal it can play an important role in the transition to low emissions. In the United States, annual carbon dioxide emissions have fallen 12% in the last seven years. The widespread opinion of energy experts is that the biggest factor is the switch from coal to natural gas to generate electricity, and there is still a long way to go.
In light of this, I envisage that natural gas electricity will be a long-term contributor to our energy mix, making possible the large-scale uptake of intermittent renewable sources.
Fortunately for this scenario, the size of worldwide and Australian natural gas reserves is huge. In a report published last year, Australia’s national science agency, the CSIRO stated that “Western Australia alone was estimated to be holding the fifth largest reserves of shale gas in the world – approximately double the amount of gas held in WA’s offshore conventional fields”.
ONE MORE THING – I almost forgot another “supply” of clean electricity, with none of the problems of the other energy sources. This secret energy source is called “efficiency”.
In a mathematical sense, reducing the load by improving efficiency is just the same as increasing production by building zero-emission electricity generators. Without doubt, efficiency is the most important fuel supply of all.
We’ve already started to mine this supply. With ongoing innovation to make our buildings better insulated, our machines more clever, and our lighting and computing less energy hungry, I see no reason why we cannot continue to make more energy savings as time goes on.
Innovation will drive this continuous improvement. We must never underestimate the ingenuity of mankind to innovate and find new, better ways of doing things. Many people see rising greenhouse gas levels as a doomsday scenario. I don’t, because I am convinced we can solve the problem by the application of human ingenuity.
The world did not run out of food in the 1960s. The world did not run out of oil in the 1970s. The world did not destroy itself in nuclear Armageddon in the 1980s. And computers did not stop shrinking in the 1990s. So, too, human ingenuity can find increasingly clever ways of getting more from our energy resources while continuing to reduce the greenhouse gas emissions profile.
WHERE WILL ALL this bring us? What must we achieve to make me satisfied that I am a citizen of the Electric Planet?
Realistically, we will never convert 100% of our energy consumption to electricity, at least not in the next fifty years. For example, I cannot imagine in my lifetime boarding a battery-powered aeroplane to fly 13,000 kilometres from Melbourne to Los Angeles.
My definition of the Electric Planet, then, is based on a stretch goal instead of perfection. That goal is for 70% of our total energy consumption to be supplied by low emissions electricity – a national grid average emissions intensity of less than 200 grams of carbon dioxide emitted per kWh of electricity generated, significantly lower than today’s average in Australia of 850 grams per kWh.
Through a mix of renewables and natural gas electricity, this will be achievable.
Some countries have already done better. In France, where 90% of the electricity comes from nuclear or hydro sources, the grid average mix is just 85 grams per kWh, ten times lower than the present level in Australia.
So, what is required to achieve the Electric Planet 50 years from now?
We need, of course, a national strategy. But before we can develop a strategy, we need to agree on the vision. I offer the Electric Planet as the vision.
We face an enormous challenge to bring greenhouse gas emissions under control. I urge our government, industry and intellectual leaders to develop a strategy that in fifty years will have us living with abundant energy, a vibrant economy and a stable environment.
Earth is the best planet we have. We should invest in its future.
This is an edited transcript of a speech delivered by Alan Finkel at the 2013 Clunies Ross Awards, hosted by the Australian Academy of Technological Sciences and Engineering (ATSE). He has a doctorate in electrical engineering, is the president of ATSE, Chancellor of Monash University in Melbourne, and a co-founder of COSMOS Magazine. The Electric Planet logo was created by Zenon Charalambous.
Click to hear Dr Finkel discuss The Electric Planet at the 2013 Adelaide Festival of Ideas, as recorded by the ABC or watch below with the slides included (best viewed fullscreen).