Global power demand today is about 12.5 terawatts, which is likely to grow to 17 terawatts by 2030, the U.S. Energy Department reports. Meeting that demand with renewable power certainly won’t be cheap. Mark Jacobson, a civil and environmental engineering professor at Stanford, and Mark Delucchi, a research scientist at the University of California, Davis’s Institute of Transportation Studies, estimate that construction of a worldwide wind, water and solar system would cost $100 trillion over 20 years, including upgrades to the grid.

But, Jacobson and Delucchi write, “This is not money handed out by governments or consumers. It is investment that is paid back through the sale of electricity and energy.” And the authors contend that because electrification is more efficient than using fossil fuels, a drop in global energy demand occurs from 17 terawatts to 11.5 in 2030.

According to a new report from the University of California at Davis and the Institute for Transportation and Development Policy, all of this spending and more could be saved if the world’s urban population made the transition from automobile dependence to reliance on mass transit, walking and cycling. (A co-benefit would be a 1,700-megaton annual reduction in CO2 emissions by 2050.) But that rosy future is dependent on a massive change in consumer behavior.

The Global Commission on the Economy and Climate puts a slightly lower price tag on the global infrastructure expenditure necessary to reach renewable energy and climate goals by 2030—$89 trillion—but also envisions $2 trillion savings to that date from “reduced investment in fossil fuel power plants in a low-carbon scenario.” And it sees further savings accruing from energy-efficiency gains, reductions in transmission and distribution investment, and drastically lower costs for fossil fuel exploration and transportation, among other things.

Those savings could add up dramatically. “Overall, the net incremental infrastructure investment needs from a low-carbon transition could be just $4.1 trillion, if these investments are done well,” said the Global Commission report. It even imagines a scenario that would result in net savings of $1 trillion. Some disagree. Ottmar Edenhofer, a German climate economist who served as an advisor to the Global Commission but was not an author of its report, told The New York Times that the assumptions necessary to reach that no-net-cost outcome are “overly optimistic.”

“The price of electricity sold to utilities under long-term contracts [in 2013 and 2014] from large-scale solar projects has fallen by more than 70% since 2008, to $50 per megawatt-hour on average.” –Mark Bolinger

High Upfront Costs

In 2011, President Obama outlined a goal of 80% renewable energy for the U.S. grid by 2035. Reaching that ambitious target could mean adding 20 gigawatts a year for 20 years, then 45 gigawatts annually until mid-century.

The Energy Information Administration (EIA) estimated that President Obama’s scenario would raise average utility bills in 2035 by 29% (higher in some areas). A megawatt-hour of electricity could rise from $9 to $26 in 2030, and from $41 to $53 per megawatt-hour by 2050, the Renewable Electricity Futures study said.

According to that federal report, “Higher electricity prices associated with the high renewable scenarios are driven by replacement of existing generation plants with new generators (mostly renewable), additional balancing requirements reflected in expenditures for combustion turbines, storage and transmission; and the assumed higher relative capital cost of renewable generation, compared to conventional technologies.”

A new “Green Growth” report from the Center for American Progress (CAP) and the University of Massachusetts Political Economy Research Institute estimates the cost of reaching a similarly ambitious goal — 40% reduction in U.S. greenhouse gas emissions from 2005 levels by 2035 — at $200 billion annually from both public and private sources (with public investment averaging about $55 billion per year).

However, the CAP report notes that the projected public spending under its plan would be only 0.3% of current U.S. GDP, and approximately 1.4% of the federal budget. Some $90 billion of the annual expenditures would go to energy-efficiency measures for buildings, transportation and industry — with the potential of reducing American energy use by 30%.

Looking to recent history for guidance, the Environmental Defense Fund (EDF) reports that there’s little evidence that a 40% increase in renewable energy on the grid since 1994 has raised electricity prices in the U.S. EDF reports that those rates have “remained steady” during this period, even as coal plant sulfur dioxide and nitrogen oxide emissions declined by more than 75%.

That Could Exceed Projections

Critics say the actual increases from committing to renewables will be higher than the federal estimates. For instance, the Manhattan Institute said in 2011 that reaching the 20% wind goal for the U.S. national grid would “impose a tax on U.S. electricity consumers of $45 to $54 for each ton of carbon dioxide that was removed,” and it claimed that electricity consumers in coal-dependent regions would end up paying as much as 48% more for electricity.”

Utility-scale solar in the U.S. has dropped from $3 per installed watt in the first quarter of 2012 to $1.85 in the first quarter of 201…. Commercial solar prices dropped 20% … and residential solar 25%. –The Solar Energy Industries Association

Meeting British renewable energy goals, said Britain’s Renewable Energy Foundation in 2014, would require $211 billion in subsidies by 2040, with peak annual costs of around $10 billion. The country’s Committee on Climate Change estimates expenditures of $10 billion per year.

The German goal of 40% to 45% renewable energy by 2025 (and 80% by 2050) is proving costly to achieve. According to the The Wall Street Journal, “Average electricity prices for companies have jumped 60% over the past five years because of costs passed along as part of government subsidies of renewable energy producers. Prices are now more than double those in the U.S.”

The International Energy Agency has put a price tag on confronting climate change at $10.5 trillion by 2030. That’s the global investment in low-carbon energy (plus energy efficiency) that’s needed, the agency estimates, to hold greenhouse gas concentrations in the atmosphere to 450 parts per million and world temperature rise to 2 degrees Celsius.

According to Mark Moro, a fellow at the Brookings Institution, “The figure $10.5 trillion by 2030 declares objectively and indelibly that the battle against climate change requires remaking the world energy system with new technologies, many of which don’t exist, or don’t exist cheaply enough, and that we’d better get to work on that in earnest.”

But Prices Are Coming Down

Yet, renewable energy costs are already dropping. The Lawrence Berkeley National Laboratory reported in 2014 that the average, upfront installed price for utility-scale photovoltaics dropped by more than a third since the 2007-2009 period, with an attendant increase in project-level performance. And, said report author Mark Bolinger of Berkeley Lab, “The price of electricity sold to utilities under long-term contracts [in 2013 and 2014] from large-scale solar projects has fallen by more than 70% since 2008, to $50 per megawatt-hour on average.”

According to Lazard Freres & Company’s “Levelized Cost of Energy (LCOE) Analysis 7.0,” LCOE for wind and solar in the U.S. has declined more than 50% between 2009 and 2013. Lazard estimates that utility-scale solar photovoltaics are competitive with fossil fuel for peak energy in much of the world, even without subsidies. The New York Times concludes that Germany’s fast-paced purchase of wind turbines and solar panels is bringing large Chinese manufacturers into the space and “driving down costs faster than almost anyone thought possible just a few years ago.” That development is threatening to electric utilities, which have seen few challenges to their business plans.

According to the Solar Energy Industries Association, utility-scale solar in the U.S. has dropped from $3 per installed watt in the first quarter of 2012 to $1.85 in the first quarter of 2014. And, in the same period, commercial solar prices dropped 20% (to $3.72 per watt) and residential solar 25% (to $4.56 per watt).

Wind farms are also competitive. Bernard David, an entrepreneur and author who is also a senior fellow at Wharton’s Initiative for Global Environmental Leadership (IGEL), agrees that, although there are some technical constraints, the aggressive Chinese push into renewable energy is bringing with it the economies of scale necessary to compete with fossil fuels.

Wind costs have dropped 90% since 1980 and, reports the Motley Fool, “Wind energy is now cheaper than many conventional fuels.” According to Mandy Warner, an EDF climate specialist, “New coal-fired power plants are one of the costliest generation options even without considering the significant pollution they generate. If built in the next five years, they would cost about 19% more than onshore wind, 44% more than combined cycle natural gas, and significantly more than energy-efficiency measures.”

Targeting Coal

Addressing coal-burning power plants has become an effective strategy for reducing emissions, and the Obama Administration’s Clean Power Plan aims to cut U.S. power carbon by 30% below 2005 levels. And EPA modeling shows that implementation of its Clean Power Plan for older coal plants will result in bills $8 per month lower in 2030 than they would be without the plan.

Just $50 billion “is the surprising low price to buy up and shut down all the private and public coal companies in the U.S., breaking the centuries-old grip of an obsolete, destructive technology that threatens our present and our future.” –Felix Kramer and Gil Friend

In The Guardian, Felix Kramer and Gil Friend report that $50 billion “is the surprising low price to buy up and shut down all the private and public coal companies in the U.S., breaking the centuries-old grip of an obsolete, destructive technology that threatens our present and our future.” The authors claim that such a move would “generate $100 to $500 billion in benefits every year,” and imagine “a few shrewd and enlightened investors” taking the lead on funding and structuring the Coal Buyout Fund.

 The Path Not Taken?

And any analysis of energy generating costs has to include consideration of the costs of not taking the renewable path. That’s the focus of the Risky Business Project, co-chaired by former New York mayor Michael R. Bloomberg, former Treasury Secretary Henry Paulson and hedge fund manager/environmentalist Tom Steyer.

“If we continue on our current path,” the report says, “many regions of the U.S. face the prospect of serious economic effects from climate change.”

  • Because of higher sea level and aggravated storm surge, the average annual cost of coastal storms on the eastern seaboard and the Gulf of Mexico could reach $3.5 billion in 15 years, with hurricane activity taking that figure to $7.3 billion. By 2050, $66 to $106 billion in coastal property could be underwater, and up to $507 billion worth by 2100.
  • Midwestern and Southern farmers could see their corn, wheat, soy and cotton yields drop 10% over the next five to 25 years. There’s a one in 20 chance the losses could top 20%.
  • Temperature changes because of climate change might require the construction of up to 95 gigawatts of new power generation in the next five to 25 years. That translates to 200 coal or natural gas power plants.

Some of the projections may underestimate the cost of switching to renewables, but the more pessimistic reports probably downplay the offsetting benefits and consequences of not taking steps.