Category: pollution

Taking the Measure of Plastic Bag Bans

Taking the Measure of Plastic Bag Bans

MichaelisScientists [CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0)]

Americans go through 102.1 billion plastic bags each year, and those bags end up everywhere. Whether they’re in whale stomachs, or in our water as microplastics, the volume has people concerned.

In an effort to reduce the amount of plastic, bans on single-use plastic bags are on the rise. California and New York already have state-wide bans, and Maine has just become the third state to do so. In other states, cities like Boston, Seattle and Chicago have their own bans, and more seem likely to follow.

While it’s popular to attack plastic bags, it’s still important to ask questions to make sure the bans are necessary and effective.

Are plastic bags as bad as people think? What are the alternatives, and are they any better? What impact do these bans have on people’s behavior and the environment?

It turns out that when you look at the whole lifecycle of different bags, and the unintended consequences of the bans, the results aren’t straightforward.

Cost of Bag Production

The environmental cost of production is a good starting point in measuring the impact of different bags. Contrary to what you might think, from this perspective, plastic bags win out.

Plastic bags are made by using ethylene. Ethylene   is a by-product of the crude oil refining process and natural gas production.   Manufacturing plants have also gotten very efficient at making plastic, so this process doesn’t generate many greenhouse gases per bag.

Paper bags, on the other hand, require cutting down trees and then processing them in an energy-intensive way. A 2005 Scottish study noted that paper bag production uses about four times as much water as plastic and creates three times the amount of greenhouse gases. It should be noted that in the United States, many paper manufacturing facilities use biofuels and co-gen systems to generate the power used in the manufacturing process which may mitigate some of these emissions.

Even cotton tote bags aren’t better for single use. This is because you need to factor in the land and water used to grow the cotton, as well as the processing and production. One study found that you’d need to use the tote bag at least 131 times to be better than a single-use plastic bag, based on the production impact.

Recycling and Decomposing

One of the biggest problems with plastic bags is what happens after they’re used. This is true whether they’re used once or a couple of times.

While the bags can technically be recycled, municipalities don’t accept them with other recyclables. This puts the burden on the consumer to save them and bring them to a place that will accept them, and most people don’t go to the trouble.

When plastic doesn’t get recycled, it either goes into a landfill or ends up as litter.

In a landfill, plastic takes an average of 500 years to decompose. The volume of these bags in the trash also comes at a cost. California alone spends $25M annually on disposal of plastic waste in landfills.

Paper, on the other hand, decomposes in just two to six weeks. It can also be easily recycled.

Other Impacts of Plastic in the Environment

Additionally, when plastic ends up as litter, the environmental impact is much worse than with paper.

Plastic has become one of the most common kinds of waste products, with much of it ending up in the ocean. A study from UC Santa Barbara found that each year, the world’s oceans receive almost 8 million metric tons of plastic.

As an example of how widespread this is, a recent dive by American explorer Victor Vescovo found a plastic bag at the bottom of the Mariana Trench, seven miles below the surface.

One of the biggest concerns with this is the impact on marine animals. Many are tempted to eat plastic bags, thinking they’re food, but instead the bags block their digestion.  As many as 1 million sea animals die each due to the plastic in the oceans. Among them was a dead sperm whale found in April 2019 with 48 pounds of plastic in its stomach.

A less publicized issue is the fact that plastic bags can cause problems in urban settings by clogging waterways and drains. This was discovered as one of the primary factors in flooding in Bangladesh in 1988 and 1998, which led them to ban plastic bags in 2002.

Microplastics are another concern. These form when the plastic breaks down into smaller and smaller pieces.

No one has enough evidence to show any specific health impacts of microplastics, mostly because it is unethical to ask human test subjects to ingest microplastics due to known health hazards of plastic in general, but the amount and range makes it worth watching. A 2017 study found that 94% of tap water samples from the United States contained microplastics and other studies have found high concentrations of microplastics in fish and shellfish commonly eaten by humans.

Another study also noted that when plastic bags are exposed to sunlight, they begin to give off ethylene, and continue to do so even after the sun sets.  This ethylene can contribute to the creation of atmospheric carbon monoxide, a greenhouse gas.  

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These factors are what make the plastic bag bans so popular, even though from a production standpoint, they can do less environmental damage than the alternatives.

Considering Consumer Behavior

One issue that policymakers often overlook is how consumers will react to their policies. Production and disposal are only one part of the story. It’s also important to consider if people actually do reuse those bags, for what purpose, and how consumers will change their behavior after a plastic bag ban.

In some cases, people do use the plastic bags again, though often only one other time. The most common examples are to line small trash cans and to pick up after dogs. Those needs don’t disappear with the bans, and those are things you can’t use tote bags for.

As a result, one side effect of the bans is that people buy more trash bags for those purposes. Rebecca Taylor, an economist at the University of Sydney, saw a 120% increase in sales of small, four-gallon trash bags. From an environmental perspective, trash bags are worse than the single-use bags, since trash bags are thicker than grocery bags. This means they use more plastic, and it takes longer for them to degrade.

A quick glance at the comments section of the Portland Press Herald, in an article announcing the ban, revealed that many commenters were “hoarding” their plastic bags in response to the ban, or even buying rolls of plastic bags in advance of the law’s April 2020 effective date.

Additionally, the use of paper bags increases significantly after bans. A survey of a few areas in California found that paper bag usage jumped from 3% to 16%. This meant increased production for paper bags, as well as higher volumes of paper trash.

Still, the bans do encourage people to reuse bags by 40%. The bans also reduce the amount of plastic that ends up as trash, which is the other piece to consider.

Conclusion – It’s Complicated

Economists are notorious for responding “it depends” when asked a question comparing two alternatives.  The impact of bans on plastic bags is no different.  Depending on what you measure, you can find support for using plastic bags, and support for banning them.   

It’s important to remember that the impact doesn’t stop with the manufacturing. It continues with how the bags are used, and what happens with them when they’re no longer in use. It’s also important to recognize that no law is ever passed in a vacuum. We need to consider how people will respond, what alternatives are available to them, and what the unintended consequences may be.   

References:

Defining Safety Levels for Particulates Could Hurt Your Health – and the Economy

Defining Safety Levels for Particulates Could Hurt Your Health – and the Economy

You’ve probably heard about some of the recent changes from the Environmental Protection Agency (EPA). But you might have missed the proposal about particulate matter (PM), since it didn’t get as much press. Or even if you saw it, you might not have recognized all the implications because they’re not immediately obvious.

This proposal is to define a safety threshold for what’s called PM 2.5, and it’s a reversal of the EPA’s prior stance. Until recently, the EPA said that no amount of particulate matter can be considered safe. Changing that could have serious impacts on our health – and the economy.

What is PM 2.5, and where does it come from?

Even if you’ve never heard of particulates, you’re likely familiar with them. These are the fine particles of liquids and solids that contribute to haze-filled cities and poor air quality. In fact, another name for PM is particle pollution.[1] This is because the tiny size allows these particles to get everywhere – including deep in your lungs.

PM 2.5 is a specific kind, named because the particles are only 2.5 micrometers in size. For comparison, an average human hair is 75 micrometers in width.[2]

These tiny materials are everywhere, coming from a number of places, including cigarettes and fireplace smoke. But the vast majority come from two sources:

–          50% is from industrial production, with 20% of that from coal-powered plants

–          35% is from gas-powered vehicles of all kinds[3]

Costs and benefits with current policy 

Under the current policy, with no level of particulate matter considered “safe,” any reduction of PM 2.5 below current levels is considered a benefit, and can be included in federal cost-benefit analyses.

In other words, if regulations to reduce greenhouse gases simultaneously reduce PM 2.5 (as they would, given that they share many of the same sources), that reduction counts as a co-benefit. And those co-benefits can play a significant role in the cost-benefit analysis of any proposed regulation to reduce greenhouse gases.

For example, the Clean Power Plan from the Obama era had an estimated $20 billion in climate benefits. But the benefits go up when you consider that the same technology used to reduce power plant emissions would also cut PM levels. Those changes result in an additional $13 to $30.3 billion in health benefits, effectively doubling the benefits.

Similarly, the Mercury and Air Toxics standards save $4 to $6 million by reducing toxins. And in this case, the co-benefit from reducing particulates is even higher, coming in between $37 and $90 billion.[4]

Proposed change reduces benefits

Now, under the proposed changes, lowering PM levels below the suggested “safety levels” won’t count as a benefit. After all, if anything below the threshold is already considered safe, bringing it down even further won’t be helpful.

This means that moving forward, climate change initiatives like the Clean Power Plan wouldn’t be able to factor in the lower levels of PM 2.5. And without that, the initiative might not get implemented, because the cost would be considered too high without the co-benefit to offset it.[5]

Damages from air pollution

 The impact on regulations is a concern, but those aren’t the only considerations. Air pollution already causes damages between $75 and $230 billion annually. And PM 2.5 contributes more to that than their size indicates.

Even though these particulates only account for 6% of emissions by weight, they cause 23% of the damages. The damages from PM 2.5 alone are between $17.25 and $52.9 billion annually. [6]

Health and economic impact

Most of the economic damage caused by PM 2.5 is due to increased health costs.[7] Health issues associated with PM 2.5 include:

–          Respiratory illnesses like bronchitis

–          Premature death

–          Low birth weight

–          Higher risk of asthma

–          Greater risk of heart disease

–          More instances of lung cancer

These conditions all carry increased economic cost. Some of this is a result of increased medical care, such as hospital visits and medication. [8]

But the costs also come from lost work time and reduced productivity. People who need to take time off for appointments and medical care won’t be as effective. Similarly, those who can’t breathe as well have less energy and will be less productive, even if they don’t require urgent care.

In addition, since particulates contribute to poor air quality, people might be more likely to stay inside. This means lost revenue from outdoor recreation and the potential of reduced health from lower levels of activity.

Poor air quality actually could have a negative impact on region’s workforce. Putting a priority on quality of life is becoming more common – including looking at factors like air quality. If an area has a distinct haze, or higher levels of respiratory conditions, people may choose to leave, or to not move there to begin with.[9]

Conclusion

While it’s impossible to identify all the effects of the EPA’s proposed safety threshold, it’s clear that the negative impacts could be far-reaching. Given that, the EPA and other agencies should take all of the risks into account before accepting a change that could cause such extensive damages to our environment, our health, and our economy.

Photo Credit:   Eltiempo10 [CC BY-SA 4.0], from Wikimedia Commons

[1] https://airnow.gov/index.cfm?action=aqibasics.particle

[2] http://www.sciencemag.org/news/2018/08/kill-climate-rule-trump-s-epa-wants-redefine-danger-soot

[3] http://www.rff.org/blog/2007/what-do-damages-caused-us-air-pollution-cost

[4] http://www.sciencemag.org/news/2018/08/kill-climate-rule-trump-s-epa-wants-redefine-danger-soot

[5] Ibid

[6] http://www.rff.org/blog/2007/what-do-damages-caused-us-air-pollution-cost

[7] Ibid

[8] https://www.brookings.edu/blog/jobs/2011/05/06/we-are-what-we-breathe-the-impacts-of-air-pollution-on-employment-and-productivity/

[9] https://www.forbes.com/sites/quora/2018/05/29/how-the-air-quality-where-you-live-might-be-affecting-your-health/#2881f8b37017

Keeping the Lights On Doesn’t Mean More Pollution

Keeping the Lights On Doesn’t Mean More Pollution

Photo – Creative Commons/Flickr Amy the Nurse

In August of 2017, Energy Secretary and former governor Rick Perry proposed to strengthen subsidies to coal- and nuclear-fueled electricity plants.  Why?  According to his proposal, coal and nuclear power plants are indispensable to our national security by virtue of the fact that they can store energy on-site. And, since the past few years have seen declines in both coal and nuclear facilities in the United States, the concern is that the nation’s electricity grid will be less reliable in the future. The proposal would have guaranteed cost recovery and a fair rate of return for generators that can store at least 90 days’ worth of energy on site.  Fortunately, the Federal Regulatory Commission rejected it.  Even so, it’s still worth looking at the pros and cons of such a proposal.

More power outages and more disruptions would, of course, harm our energy-intensive economy. As the recent spate of hurricanes (including high winds in my home state of Maine) have shown, such energy disruptions can be costly. In fact, 2017 was the costliest year in terms of economic damages from natural disasters in the US.

Would subsidizing coal and nuclear facilities really have been the best solution? To answer that, we need to take a deeper look.  When I teach cost-benefit analysis, I encourage my students to consider the baseline – what would have happened in the absence of the policy or proposal in question. The number of coal and nuclear plants in this country has been declining for decades. The decline can be attributed to several factors, including environmental regulations, but mainly the declines are due to market forces (low electricity prices, declining electricity demand, and new supplies from natural gas) and aging infrastructure. Without taking a close look at the finances of the plants in question, we can assume that at least some of these plants would have been likely to follow.  Increasing subsidies to already struggling nuclear and coal plants would likely have been just another case of throwing good money after bad.

When considering the costs and benefits of the proposed plan, there would have been several different categories, each accruing to different groups.  The beneficiaries of the plan would likely have been owners and shareholders of the qualifying coal and nuclear plants.  Their consumers, as well, may have benefited from a lower average wholesale price of electricity; however, the proposal recommended adding a surcharge to consumers’ bills in order to cover the costs. According to the analysis done by Resources for the Future, the drop in the wholesale price of electricity would not have been enough to cover the surcharge.

Moreover, practitioners of cost-benefit analysis need to carefully consider all the costs and benefits of a proposal, not just those that are easily monetized.  A complete analysis of the costs and benefits of Secretary Perry’s proposal should include the damages caused by pollution from coal and nuclear-powered plants to humans and agriculture. (While the generation of electricity from nuclear plants does not create air pollution, the mining for uranium does create environmental destruction.) Such external costs are in reality a passive subsidy that coal and nuclear plants have enjoyed for decades. An additional subsidy would exacerbate the problem. According to the analysis done by Resources for the Future, the proposed plan would have immediately increased sulfur dioxide and nitrogen oxide, two pollutants generated by the combustion of fossil fuel.  This increase in emissions is linked to an increase in premature deaths caused by respiratory diseases such as chronic bronchitis and emphysema. Once environmental costs are factored in, net benefits to society would have been decidedly negative.

The next question is: would the subsidies have alleviated the problem of grid instability? The answer to this question actually lies in the question itself.  Is there really a problem of power disruption caused by declining coal and nuclear plants? Some recent research by the Rhodium Group says no.  Researchers examined the data collected by the Department of Energy whenever an electricity generator experiences an outage or a disturbance.  Results indicate that disruptions in fuel supply were responsible for less than 1 one hundredth of one percent of lost customer service hours between 2012 and 2016.  The remainder were caused by disruptions to energy distribution  Primarily, those disruptions were caused by severe weather, not by supply disruptions.  The FERC ultimately agreed when it rejected Secretary Perry’s proposal.

However, the FERC did agree that the reliability of the grid was an issue looking into.  If the goal of Secretary Perry’s proposal was to increase the reliability of the grid – not just to prop up nuclear and coal – there are several less costly and ultimately beneficial ways of doing so.  One such possibility is to replace our nation’s aging energy-related infrastructure, much of which dates to the 1950s and 60s. Energy infrastructure actually received a “D+” on the 2017 report by the American Society of Civil Engineers. Upgrading the energy infrastructure would come with many ancillary benefits.

A second alternative would be to invest in distributed energy and microgrids.  Distributed energy is the use of small, decentralized power generation and storage systems. While larger utilities consider the rise of distributed energy to be a threat to the existing system, the greater use of distributed energy could actually increase the resilience of our current, outdated system.  However, doing so will require innovations in monitoring, modeling, “smart switches,” and other technologies to manage peak demand and integration.

A third possibility is to invest in better long-term energy storage. Lithium ion batteries may be our best choice for now, but other storage technologies, such as flow batteries or zinc air batteries.  But by far the best alternative – one that should be a crucial part of any solution – is energy conservation.  A unit of energy conserved is one that doesn’t need to be generated.  You don’t get much more reliable than that.

Woody Biomass: One step forward, two steps back?

Woody Biomass: One step forward, two steps back?

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Last week I was a guest in my colleague’s Renewable Energy Law class.  One of the questions I was asked had to do with Maine’s Renewable Portfolio Standard (RPS).  Maine’s RPS seems, at first glance, to be an ambitious goal (40 percent of Maine’s electricity is to come from renewable sources by 2017). However, at the time the RPS was made law, Maine was already mostly meeting that goal, thanks to Maine’s booming woody biomass industry. 

Other states in the New England Power Network can help fulfill their own RPS by purchasing renewable energy certificates (RECS) from other states in the network.  If a particular unit of energy is produced by a renewable source, that unit of energy could earn a REC, which could then be sold elsewhere.  However, even though every state in New England has a RPS (except Vermont, which has a goal), they don’t all accept the same types of energy for their RPS. Hence, there are some RECS that can be sold in some states, but not others.

Maine is the only state in New England that accepts biomass and large scale hydro to help fulfill its RPS. Therefore, any biomass facility that produces RECS can only sell them in Maine. In a report that came out detailing the performance of Maine’s RPS during the past year, a good 95% of the  Maine RPS was met through RECS generated from biomass.  And the fact that biomass credits can only be sold in Maine will depress the price of those credits -leading to less revenue for those facilities.

Which lead to one of the students’ questions: why don’t the other states accept biomass?  It’s a good question.  Leaving aside the (obvious) conclusion that Maine accepts biomass as an energy source in order to prop up its ailing wood products industry, why would other states not accept it? Isn’t biomass a renewable source of energy? And isn’t it carbon neutral ?

The answer, as any good economist knows, is “it depends.”  (My father used to say -paraphrasing Harry Truman – that what the world needs is a one-handed economist, because we’re always saying ”on the one hand….  But on the other hand…” ) Biomass is certainly a renewable source, in the strict physical sense that the “fuel” used – plant matter – is renewable.  The time it takes to regenerate, of course, depends on the growth rate of the plant matter used.

But there’s also no escaping from the grim third law of thermodynamics – that matter (or energy) can neither be created nor destroyed.  It takes power to make power.  How efficient the energy source is depends upon the energy content of the fuel and the energy used up in the process of making it.  Think lifecycle analysis.  If a unit of energy generated requires two units of energy in order to generate it, then that source isn’t really renewable – is it?

UPDATE: As my colleague Bill Strauss of FutureMetrics points out, “Every solid or liquid fuel whether coal, pellets, gasoline, diesel, natural gas, etc., gathers a carbon footprint from mining, extraction, refining, transport, etc.  Only biomass, if the net carbon stock is not depleted (i.e., the growth rate equals or exceeds the harvest rate), captures the CO2 from combustion contemporaneously…  Wood pellets are a low carbon solution… they are carbon neutral in combustion but are not carbon neutral over the supply chain.  Of course neither is anything else that depends on fossil fuel for transport etc.”

Absolutely, Bill, and thanks for that. (So people actually do read this stuff…) Check out their website!

Biofuel can be made from a number of things: corn, switch grass, trees, wood  manufacturing waste, to name a few.  And there are a number of ways biofuel can be produced – burned, fermented, digested by bacteria, or “gasified.”  The energy content of the fuel as well as the energy input needed vary widely for each process. 

As for whether it’s carbon neutral – well,  anyone who makes that claim is doing some pretty funky carbon accounting.  In the sense that the carbon released when the tree is burned is the same amount of carbon that was “stored” in the tree – then yes. But what about the carbon used in harvesting the tree?  Getting it to the processing site,  and from there to where it will ultimately be used? There’s also the fact that trees uptake carbon at different rates in their lifecycle, and that different species of trees uptake carbon at different rates. So for it to be carbon neutral, the net stock of carbon in the forest needs to remain unchanged. It’s possible, but it’s not as simple as “cut a tree, plant a tree.”

What about the claim that it’s sustainable? Again,  it depends.  If the trees are harvested at the same rate they regenerate, then yes. And, Maine’s biomass is mostly from residue from the forest products industry, so the use of waste product for energy gets a thumbs up in my book.

Recently,  two major biomass facilities in Maine went offline,  alarming the logging industry and others in the forest products supply chain. It also should alarm environmentalists.  The decline in oil prices has not only boosted demand for oil,  but depressed demand for biomass and other renewable sources of energy. Biomass may not be a perfect source of energy,  but it needs to be part of the energy solution in Maine.