Industry Market Trends

The Damage Done -- Is There an Energy Future That Doesn't Ruin the Planet?

May 07, 2012

By 2030, the world economy will have 3 billion more middle-class consumers, says a report from management consulting firm McKinsey & Co., (Resource Revolution: Meeting the world's energy, materials, food, and water needs,November 2011). Those 3 billion people will expect to have energy available to them; they'll need to heat and cool their homes, run their appliances and home electronics, drive their vehicles and consume food and products that require energy to produce.

McKinsey & Co. forecasts that, aside from this emerging middle class, all people around the world should have access to clean, reliable and affordable energy services for cooking and heating, lighting, communications and productive uses for a cost of a marginal $50 billion a year over the next 20 years.

Such universal access to basic energy services would require about 7 quadrillion British thermal units (QBtus) per year, an increase over the base case of only 1 percent.

The future envisioned by McKinsey & Co. is a world with a much greater energy demand. In fact, global energy consumption is projected to climb from 542.3 quadrillion British thermal units (QBtus) today to 721.5 QBtus in 2030, according to data from the U.S. Energy Information Administration(EIA).

Photo of sculpture of a sad earthHow will that affect the environment? Is there a way to provide the world's burgeoning population with the energy it will need without causing more environmental pollution and climate change and thereby making the planet unlivable? (Photo: Sad Earth. Credit: John LeGear, CC BY-SA 2.0.)

Over the past few months, I've penned a series of "Damage Done" articles about the effects of the production and consumption of both conventional and green energy. This article is the final one in the series.

The series grew out of discussions with Green & Clean readers about the relative merits of green energy versus conventional energy sources. Inquiring minds wanted to know how we can be certain that green energy is really greener? Is it possible that so-called renewable energy pollutes the Earth just as badly as fossil fuels?

Photo of wind farm in MexicoAfter researching this topic extensively, I feel confident in saying that nuclear power and renewable energy (wind, solar, geothermal, etc) definitely produce less pollution and emit lower levels of greenhouse gases (GHGs) than do fossil fuels (coal, petroleum, natural gas). The environmental damage of nuclear and renewables is not zero, but it is definitely lower. You're welcome to dig deeper and find out what led me to that conclusion by reading my two primary summary articles in the series:

Summary piece on electrical generation: "The Damage Done, Part 10 - Are Renewables Really Better for the Environment Than Fossil Fuels?"

Summary piece on transportation energy: "The Damage Done in Transportation - Which Energy Source Will Lead to the Greenest Highways?"

(Photo: Wind farm in Oaxaca, Mexico. Credit: Walmart Stores, CC BY 2.0.)

In the transportation sector, electric and hydrogen vehicles are often presented as green technologies. However, as I've pointed out in my previously articles, the environmental friendliness of these technologies depends largely on the electric grid and its ultimate energy sources -- see my articles "The Damage Done - Electric Vehicles, the Green Way to Get Around?" and "The Damage Done - Hydrogen Vehicles, Good for the Planet?"

A transition to cleaner energy over the next 30 to 40 years looks feasible though costly. Below is some research that shows a bit on how it might be done. As I've done throughout the "Damage Done" series, I base my arguments on reasonable calculations of projected energy demand and consequent environmental impact.

Monetized Environmental Damages From Energy: The Pennies Add Up

The NEEDS study(New Energy Externalities Developments for Sustainability) provides calculations on environmental damages from electrical energy sources, including health impacts, biodiversity loss, crop yield loss, material damage, and land-use damage. The following table shows the total external environmental costs of various energy sources, expressed in Year-2000 Euro-cents () per kilowatt-hour (kWh).

Bar chart showing environmental costs by energy source, 2009, 2025, 2050

As you can see, the damages for coal power (blue) are much higher than those for natural gas, nuclear and the renewables. To see how much money is involved, let's imagine a Year-2025 world in which all power were to be provided by coal (assuming damages of 1.18 cents/kWh), then a world entirely powered by natural gas (damages of .29 cents/kWh), followed by a world powered completely by nuclear and renewables (.07 cents/kWh). This table shows the environmental damages according to each scenario:

Estimated Damages in Y2000 /kWh

2025 Projected Global Power Consumption in terrawatt-hours (tWh) (International Energy Agency's "World Energy Outlook 2010," p. 218)

2025 Total Yearly Damages (Y2000 Euros)

100% Coal

0.0018

23,180

273 billion

100% Natural Gas

0.0029

23,180

67 billion

100% Nuclear and Renewables

0.0007

23,180

16 billion

You can see from these figures that a world that derived all of its electricity from nuclear power and renewable sources would suffer an order of magnitude less damage than a world powered entirely by coal. The calculable damages from an all-coal scenario would amount to more than a quarter of a trillion Euros per year (currently, one Euro equals about US$1.31). Damages from natural gas, a cleaner-burning fossil fuel, would only be a quarter those of coal.

The 450-ppm Scenario: Heading Off Climate Change?

A presentation from the International Energy Agency (IEA) based on the "World Energy Outlook 2011" report includes the following chart, which shows what would be required to keep atmospheric CO2 concentration from going above 450 parts per million (ppm). As you can see, CO2 emissions would not be able to go much above the approximately 30 gigatons (Gt, or a billion metric tons) per year emitted in 2010 and would have to decline to about 22 Gt per year by 2035.

IEA graph showing CO2 emissions through 2035

Current thinking is that atmospheric concentration of CO2 needs to stay below 450 ppm to prevent the average global surface temperature from rising more than 2 degrees Celsius above pre-industrial levels. This was the goal established at the United Nations Climate Change Conference 2009in Copenhagen, Denmark (COP15). A science summaryfrom the COP15 website warns:

The average temperature of the Earth's surface has risen by 0.74C since the late 1800s. It is expected to go up another 1.8C to 4C by the year 2100 if no action is taken. That's a fast and intense change in geological time. Even if it "only" gets another 1.8C hotter, it would be a larger increase in temperature than any century-long trend in the last 10,000 years.

Keeping CO2 down to 450 ppm frankly looks like a tall order, given current trends. In fact, according to the the Global Carbon Project, annual emissions grew at an average 3.1 percent per year from 2000 to 2010. As you can see from the following chart based on data from the EIA, global CO2 emissions are projected to skyrocket to 43 Gt by 2035, under business-as-usual conditions.

Graph showing CO2 emissions through 2035

Pie chart showing world energy mix 2035

It's worth noting, however, that the EIA projections for 2035 are based on approximately the same energy mix we have today, just in greater volumes. As you can see from this pie chart, the EIA assumes that dirty-burning coal and oil will still account for greater than half of global energy consumption, natural gas less than a quarter and nuclear and renewables only about 21 percent combined. What if the mix were steered toward less-polluting sources?

The table below shows CO2-equivalent GHG emissions from various energy technologies for electricity production (from Benjamin J. Sovacool writing for the journal Energy Policy.) As you can see, coal generates much higher GHG emissions than does nuclear or any of the renewables.

Source/Technology Life-cycle CO2 equivalents in grams per kilowatt hours (gCO2eq/kWh)
Coal

960 - 1,050

Natural gas

443

Nuclear

66

Geothermal

38

Solar Photovoltaic (PV)

32

Hydroelectric

10 - 13

Wind

9

As we've already seen, there's no way to be anywhere close to the 450-ppm scenario with the current mix of energy sources and given the increasing demand. What kind of energy mix might get us there?

I played around with the EIA energy consumption data and its published emission factors for fossil fuels and came up with the following three scenarios: Business-as-Usual (current energy mix), Natural-Gas (dominating at 49 percent of the energy mix), and Aggressive-Green (with nuclear and renewables commanding at 70 percent of the mix). In calculating the CO2 emissions for renewables, I had to convert Btus to kilowatt-hours and use a representative 40 CO2-equivalents per kWh as a multiplier. The total emissions estimate I calculate for 2035 is somewhat higher than that which appears in the EIA tables. (I'm happy to hear any complaints about my math and my assumptions. Basically what I tried to do here is create some broad scenarios to get an idea of what it might take to achieve the 450-ppm goal.)

Energy Mix Scenarios for 2035 (based on EIA consumption data and emission factors)

Petroleum (71.26 kg CO2/MMBtu)

Coal (103.69 kg CO2/MMBtu)

Natural Gas (53.06 kg CO2/MMBtu)

Nuclear-Renewables (est. 40 gCO2e/kWh, 1 kWh=3412 Btus)

Total Gigatons CO2

Scenario (%Petro/

%Coal/%Gas/

%Nuclear-Renewable)

Quadrillion Btus

Gigatons CO2

Quadrillion Btus

Gigatons CO2

Quadrillion Btus

Gigatons CO2

Quadrillion Btus

Gigatons CO2

Business-as-Usual

(29/27/23/21)

225.2

16.05

209.1

21.68

174.7

9.27

160.7

1.88

55.2

Natural-Gas (15/15/49/21)

115.5

8.23

115.5

11.98

377.2

20.01

160.7

1.88

42.1

Aggressive-Green (10/10/10/70)

77.0

5.49

77.0

7.98

77.0

4.09

538.8

6.32

23.9

The last row in the table suggests that, if energy demand continues to increase according to current trends, an aggressive move to 70 percent nuclear and renewable energy could keep CO2 emissions below 450 ppm.

Can It Really Be Done?

Some experts think the world really can make the transition to cleaner energy.

Amory Lovins, chief scientist at the Rocky Mountain Institute (RMI), thinks much can be accomplished through development of efficient technologies. On the RMI website, he said:

"By 2050, the U.S. can phase out its use of oil, coal and nuclear energy by using energy more efficiently and relying on natural gas and renewables to fuel the U.S. economy. The energy efficiency opportunity accounts for more than half of the business-as-usual consumption in 2050... Aggressively exploiting this opportunity makes the transition from oil and coal cost-effective, and enables a roughly one-third reduction in natural gas consumption and a major investment in renewable energy."

Energy projection graph from RMI

(Chart credit: Rocky Mountain Institute)

Earlier this year, I attended a lecture by Lovins at North Carolina State University in Raleigh. Lovins believes electric vehicles are the clean way forward for transportation. In his presentation, he gave an example of how technologies can be used to greatly improve the efficiency of automobiles:

"Let's start by making autos oil-free -- we have a lot of energy coming from the weight of cars. Epidemic obesity has made our autos heavy, and carbon fiber composites can make autos simpler, lighter and cheaper to build. The engine gets smaller, and that makes electric batteries more affordable and the costs fall. They can also be charged easier. Three interlocking technologies make this possible: advanced materials, electric propulsion and manufacturing. This shift in autos is as game-changing as moving from the typewriter to the computer. Lighter cars makes affordable the electrification of the auto industry."

Writing recently in Environmental Research Letters, Nathan P. Myhrvold and Ken Caldeira describe the results of their study of what it would take to transition from coal-based electrical generation to lower-GHG-emission (LGE) generation. ("Greenhouse gases, climate change and the transition from coal to low-carbon electricity," Feb. 16, 2012). They find that such a transition can be made, but the construction of the new facilities and infrastructure will cause up-front emissions that will delay the benefits:

"Because LGE power plants have lower operating emissions, cumulative emissions over the lifetime of the plants are lower than for conventional fossil-fueled plants of equivalent capacity. LGE power plants typically require greater upfront emissions to build, however. Consequently, rapid deployment of a fleet of LGE power plants could initially increase cumulative emissions and global mean surface temperatures over what would occur if the same net electrical output were generated by conventional coal-fired plants. Our results show that most of the climate benefit of a transition to LGE energy systems will appear only after the transition is complete."

If the effort is undertaken in the short term, say Myhrvold and Caldeira, the climate-change benefits will start to accrue in the second half of this century. They wrote in Environmental Research Letters:

"Conservation, wind, solar, nuclear power and possibly carbon capture and storage appear to be able to achieve substantial climate benefits in the second half of this century; however, natural gas cannot."

To sum it up: It seems evident that the global energy system can make a transition to an energy future that won't poison the planet and result in runaway global warming. But it won't be cheap, and it won't be painless.

Photo of solar array at vineyard in Virginia

(Photo: Solar array at a vineyard in Virginia. Credit: U.S. Department of Agriculture, CC BY 2.0.)