Coal, the most carbon-intensive fuel, is used to generate about half the countrys electricity. The big energy supply sectors are among the most capital-intensive of industries, with large-scale production and pro- cessing facilities and massive pipeline, power grid, and rail transportation networks. To achieve the 80 in 40 goal, much of this infrastructure will have to be replaced or radically upgraded. The transformation will touch everyone in the country.
It will affect transportation, housing, work lives, and even personal habits. Some of these changes will be liberating; many will improve the quality of life. But change is never easy, and we should be wary of utopian visions that promise change without pain. Of course, there is another way to cut carbon emissionsby shrink- ing the economy. Indeed, U. As long as the economy continues to grow, the most important way to reduce emissions is through innovations in the way we supply and use energy. Quantifying the innovation requirement in aggregate terms is actually a straightforward exercise.
In this exercise, we consider not the G8 goal of 80 percent which lacked a baseline year but a similar, more precisely de- fined goal also articulated by President Obama: an 83 percent reduction in U. If we assume that the U. How steep the decline will need to be depends on the rate of economic growth: the stronger the growth rate, the faster we will need to reduce carbon intensity. For example, if the U.
In other words, reducing carbon intensity can be achieved through a com- bination of 1 using fewer energy inputs to produce each unit of eco- nomic output reducing energy intensity and 2 reducing the share of carbon-based fuels in the energy mix decarbonization. But here an important caveat is in order. If compositional shifts in the U. For example, if a U. A ton of carbon dioxide has the same impact no matter where it originates. With this important proviso, the equation written above shows that decarbonization and reductions in energy intensity are substitutable: the more we can do of one, the less we will need of the other.
Project MUSE - Unlocking Energy Innovation
But to achieve the 7 percent carbon intensity reduction target, both will have to improve much faster than they ever have before. In fact, over the past 25 years, the carbon intensity of the U. The trend is in the right direction, but the magnitude is far too small. More- over, it turns out that almost all of this decline more than 1.
Q. How do I create a Gates Notes account?
Over the same period the share of carbon-based fuels in the energy supply mix hardly changed at allin other words, the rate of decarbonization was only slightly above zero. See figure 1. Now suppose that in future years the country as a whole manages to accelerate the rate of decline in energy intensity from about 1. Such an improvement might seem modest, but in fact only a handful of American states have managed it in recent years. California, whose relatively aggressive policies have made it the poster child for energy conservation efforts, achieved only a 2. And, again, if energy intensity reductions were achieved merely by shifting carbon- intensive industries to other countries with high-carbon energy systems and then importing their products, nothing would be gainedwe need real decreases.
- Mula Food!
- Clean Energy Technologies.
- Refine your editions:.
In short, sustaining 3 percent per year over many years is a tall order. Beyond Wishful Thinking Decarbonization rate Rate of change of energy intensity 0. Historical trend, Illustrative 80 in 40 scenario, Source: Lester and Finan, Still, with a strong push from government and strong public support, there is reason to be optimistic that energy intensity reductions of this magnitude are achievable. In that case, the corresponding requirement for decarbonizing the U.
What would it take to achieve that? The short answer is that it would take rapid rates of adoption of most if not all of the main low-carbon supply options: solar, wind, nuclear, geothermal, and advanced low-carbon biofuels, as well as carbon capture and stor- age CCS.
In one scenario for achieving a 4 percent per year decarboniza- tion target, , megawatts of new low-carbon electric generating ca- pacity would have to be added annually to the countrys current installed base. That is a far faster pace of new installations than the United States has managed in the past. Over the last decade, for instance, the peak year for capacity additions of all kinds was , during which 67, mega- watts were installed most of it natural gas.
Looking back a bit further, about 9, megawatts of new nuclear capacity entered service in , the peak year for com- pleting nuclear power plants. In our scenario, wind and solar power would provide 40 percent of U. This difference is caused by the intermittent nature of wind and solar power. Even when they are sited in favorable locations, wind turbines and solar systems run a smaller percentage of the time than conventional generating technologies. The remainder of the electricity required in our scenario would be provided by a combination of nuclear power and coal with CCS, together with smaller amounts of geothermal and hydropower.
One way to reduce the required rate of new capacity additions would be to rely less on solar and wind and more on higher-capacity-factor nuclear and coal or natural gas systems with CCS. Another would be to implement demand-response programs designed to shave peak power requirements by promoting conservation at peak times and by shifting electricity demand to nonpeak periods.
The deployment of grid-scale energy storage would also help. Taken together, these measures might reduce the annual requirement for new capacity additions by as much as 50 percent, but even this more modest goal would be difficult to achieve. Of course, the decarbonization target could itself be reduced below 4 percent per year.
But that would mean having to raise the target for energy intensity reduction by an equal amount above 3 percent per year.
A. No, never.
So we have a double tall order: any combination of reduced energy intensity and decarbonization that hits our carbon intensity target will be difficult to achieve in practice. We might be encouraged by the example of China, which has been building new power plants unfortunately mostly coal plants at a rate of about , megawatts per year for each of the last several years. But even aside from the somewhat questionable example of China, there are many reasons to believe that the target is not out of reach, if we put our minds to the task.
There are enormous oppor- tunities for innovation in energy efficiency and decarbonization that have the potential to yield a low-carbon energy system that is more reliable and quite possibly more affordable than the one we have now. We will shortly return to this theme and sustain it through the rest of the book. But it is worth considering the alternatives. If the United States and oth- er nations fail to stabilize the atmospheric carbon dioxide concentration at roughly the ppm target level, and if the earths climate system is no more forgiving than the best models predict, then humanity would have a different choice: we could either anticipate failure and invest ahead of time in actions that might help us adapt to climate change with less pain, or we could simply decide to live with the consequences of failure when they arise.
- Come Look With Me Through The Eyes Of A Child!
- 7 editions of this work.
- Heidi Heckelbeck Is Ready to Dance!.
In fact, even if the United States sets a course to achieve 80 in 40, investments that would enable us to adapt to climate changeto manage the unavoidable in presidential science advisor John Holdrens wordswould still be prudent, since some warming would continue to occuralbeit on a much less disruptive and dangerous trajectory. The scenario described in the previous section points to another impor- tant feature of the transition: decarbonization will mean a much larger role for electricity in the U.
Many of the most promising low-carbon technologies are much better suited to electricity generation than to the direct production of heat or other forms of energy. Nuclear, wind, and solar technologies as well as CCS fall into this category. Natu- ral gas without CCS and possibly also second generation biofuels i. Electricity consumption as a share of overall energy use has been grow- ing steadily ever since Thomas Edison launched the era of commercial electric power at the end of the nineteenth century.
Today 41 percent of Americas primary energy supply domestic and imported is used to produce electricity, compared with just 18 percent fifty years ago.
For households, businesses, and industries, electricity has become the pre- ferred energy carrier for a vast range of uses. The information technology revolution and the devices it has spawned have further accelerated this trend. Digital data centers, for instance, which barely existed two decades ago, accounted for 1.
In our scenario, electricity use would nearly triple between now and , even with substantial efficiency improvements. Transportation accounts for nearly all of this increased demand, as the vehicle fleet shifts away from petroleum. Our scenario stands in stark contrast to business-as-usual scenarios that predict only minimal changes in the transportation sector and slow growth in electric- ity demand in the coming decades. Ethanol derived from corn is the dominant biofuel in use today, and it will likely be the primary fuel used to meet a federal renewable fuels requirement in the near term.
Unfortunately, the carbon footprint of corn ethanol is greater than that of gasoline, once the whole fuel cycle is taken into account, including the energy inputs to grow the corn and convert it into fuel as well as the indirect impacts on land use and food markets. If these technolo- gies mature quickly, they have the potential to cut transportation sec- tor carbon dioxide emissions significantly, without requiring a complete overhaul of the petroleum-based infrastructure. Progress toward com- mercializing second-generation biofuels has been slow, however.