Today we’re going to discuss in detail some of the key technological challenges that must be met to achieve the deep decarbonization of our energy systems. This is a very important theme of this course. And in fact, also a very important era for action at the international level because we’ve stressed many times now the importance of developing these new low carbon technologies in addition to the ones that are already available today and already deployed to realize the deep transformation of our energy system that is required.
As I hope you remember, at the end of Lecture that (see The Deep Decarbonization of Energy Systems IV )I presented you the results of a global mitigation scenario that achieves a level of CO2 emission reductions consistent with the objective of limiting the temperature increase below 2-degree Celsius. And we saw that achieving deep decarbonization was certainly challenging, but also very feasible and required in particular the almost complete Decarbonization of electricity supply, the largest source of CO2 energy emissions today. But also the very significant, although less radical emission reductions in the end use energy sectors such as transport, building or industry.
But if you remember correctly, I also emphasized that the implementation of the scenario depended on the deployment and the development at scale of technologies that are either not yet completely technologically mature, or whose costs are still very high. And today in this lecture, starting with this first chapter I want us to identify which of these technologies in particular are key to the process of deep decarbonization. But I also want us to go through each of these technologies one by one and review which are the main technological challenges that must be overcome if these technologies are to be eventually deployed at scale.
Make no mistake here, many of the technologies that are required to reduce the emissions from our energy systems are already available and many of them in fact are already deployed, at least at a pretty significant scale in the global economy. And this is true by the way for each of the three pillars we said were the overarching framework of deep decarbonization. So remember, improving energy efficiency, decarbonizing electricity generation and switching to low carbon fuels. In each of these three pillars we can pick many examples to make this point.
For example there are many existing technological options to improve the energy efficiency of our homes and our industries. Many options for energy efficient heating and cooling. The use of thermostat in particular can save you a lot of energy simply by turning down the temperature when there is nobody at home, or at night. Replacing the incandescent lights by light bulbs also saves a lot of energy. And there are also many options to improve the insulation of the building envelope, for example, by using double or even triple glaze windows. Appliances and electronics are also much more energy efficient than they used to be in the past.
And what I’m sure you’ve noticed, the Energy Star label can help purchasing the most energy efficient equipment. So that was for just a few by the way of a very wide range of existing energy efficiency technology.
Let’s turn to the second pillar, the low carbon electricity. Here too there are already many existing options to produce electricity in a low carbon way with either low carbon sources of energy or even completely zero sources of electricity production. Example, hydropower has been used for a very long time now and is by the way one of the cheapest way to generate electricity. Many other renewable energies are also being used, although they’re being used at different scales. Onshore or offshore wind. Solar photovoltaic or concentrated solar power. Some of them have even reached what we call the grid parity.
What is it, the grid parity? Complex term for a very simple concept. It is the cost at which the low carbon technologies are, become competitive with the other alternative forms of energy. And some of the renewable energy, certainly not all of them, and certainly not everywhere, have reached the grid parity with some of their high carbon alternatives. Nuclear power is also used by several countries, in fact close to 40 countries to generate electricity. If we go to the transport sector to discuss some of the existing low carbon technologies, there are already a wide-range of fuel efficient hybrid, sometimes even completely battery electric, light duty vehicles. So for passenger transportation there are also vehicles using ethanol produced from biomass derived sugars and starch. Lots of them for example in Brazil. And also some natural gas or electric hybrid powered buses in many of the cities around the world and by the way, not only in the developed countries but also in, in large parts of the developing world already.
So to summarize, there are already lots of energy efficient and low carbon technologies that are available today and deployed at some scale. It’s true that they might, they might not yet be deployed at a sufficient scale to reach the challenge, to meet the challenge of the deep decarbonization of our energy system, but it’s also true that they’re poised somehow to achieve much higher penetration rates in the future if we are to implement the right policies to incentivize their further deployment and in particular, the pricing of carbon that will increase the price of their high carbon alternatives.
And you can think of many, many different ways that we will discuss in the next lectures of pricing carbon, either directly through a carbon tax or through an emission trading system or even the implicit pricing of carbon through different types of regulations. But the point I want to make here is that the technologies that are commercially available today, alone, will not be sufficient, at least in many national contexts to achieve deep decarbonization, or at least they are not sufficient at reasonable costs.
The existing technologies might be able to do the job, but they will do so at a very high cost. So the development of the new technologies, some of them we’re going to be talking about in the next chapter, really offers the opportunity of lowering the overall costs, the overall investment costs of climate change mitigation.
But it will require important levels of research, development, and demonstration before we go to the deployment phase eventually. And in the next chapters, we will discuss some, not all of them unfortunately because we don’t have the time, but we will discuss some of the most promising technologies of the future. All of these technologies are known to some degree.
It’s not science fiction, not at all. But most of them are still under development of some form. Some of them have been demonstrated in pilot projects or in small commercial niches and not at very large scale. Some others are technically viable but at a way-too-high cost for their mass adoption.
Some others yet the complimentary infrastructure that is needed for their deployment and yet some others face barriers for public concerns, so lack the necessary public support for their adoption due to concerns about safety, reliability or other types of environmental impacts, because it’s very important of course to take a sustainable development perspective at these technologies and not to look only at their potential to reduce greenhouse gases emissions.
Some of these technologies might have other important environmental risks that we need to identify and hopefully be able to mitigate. So in the next chapters, let’s see how we can confront these important technological challenges.