Negative
impacts of variable renewable energy (Wind and Solar) JR173
Introduction
The wind and sun may be free, green, renewable and
sustainable. But the energy, land and materials required to harness and
utilize that energy certainly are not. Renewable power
technologies such as wind and solar
are becoming economically competitive with fossil fuels. As ecological need and
economic reality converge, renewables are going to make up an increasingly
large percentage of the world’s power supply. It’s a necessary technological
transition. But at the same time, renewables have a downside that needs to be
addressed:
Life of plants
Wind
and solar systems also break down faster and must be replaced earlier and more
often than coal, gas or nuclear power plants—which have operational life spans
of 30-50 years, and generate power about 95% of the time. Wind energy proponents
claim turbines last half that long: 20-25 years. They don’t.
A 2018 UK analysis
of 3,000 onshore wind turbines found that they generate electricity efficiently
for just 12-15 years (and maybe 25-30% of the time)—generating more than twice
as much electricity, in their first year than when they are barely 15 years
old. So wind turbine raw materials depletion and land use impacts are far
higher than advocates have admitted. These realities are no better for solar
installations.
All
of this also means the cost of wind and solar electricity is far higher than
their advocates admit
.
Rare-earth, metals.
To read more about rare earth metals : Negative Impacts of Renewable Energy.docx , https://javedrashid.blogspot.com/2018/10/rare-earth-metals.html
Rare-earth elements are used in virtually all electronics.
This includes solar panels, which require rare earth metals such as yttrium or
europium, and wind power, which uses vast quantities of neodymium in the
magnets that help convert wind energy to electricity.
Rare earth elements
are actually fairly abundant in the Earth’s crust. But these metals are
typically found in extremely low concentrations. That means a lot of
destructive mining for minimal effect. Rare earth mining produces large
quantities of contaminated mine waste, creating a disposal problem.
Additionally, many of
the most productive rare earth mines are in countries with weak environmental
regulations. Political instability and national security concerns provide
further risks to long-term supply. Accordingly, Smith writes, recycling these
elements is big business, employing thousands of mostly unskilled workers
worldwide. Formal, supervised recycling processes are needed to safely dismantle
and recycle the materials, in contrast to the informal recycling systems that
are currently in place. These informal systems are cheaper but may expose
workers to health risks. Even so, the formal and informal economies often work
in tandem. Smith suggests charging a fee upfront so electronics producers and
consumers have to pay for the costs to properly recycle these products. The
most efficient solution would be to reuse electronics when possible. One
positive trend is that reuse is becoming more and more common. Smith suggests a
global collection system to maximize reuse and keep electronic waste away from smugglers
and illegal disposal.
Another idea
suggested by scholars Robert U. Ayres and Laura Talens Peiró is maximizing “material efficiency” for rare earths and other crucial
materials. Currently, when high grade ore is mined, lower
quality ores or unwanted side materials, the mining equivalent of fisheries’ by
catch, are excavated but not used. In addition to recycling, finding uses for
these mining byproducts could potentially reduce waste in the electronic and
renewable energy sector. One drawback is that some of these lower-grade
materials are energy intensive to collect, given the low yield.
In the short term,
the risks of mining rare earth elements do not outweigh the benefits of
renewable power, but improvements are needed. And when it comes to each
individual’s impact, forgoing that latest smart phone upgrade may just be the
best thing you can do.
Impact of Wind turbine vibrations on
Ground water and Shale
Ground
water contamination has been reported from Canada, from areas where the bedrock
is comprised of shale,. This needs to be investigated as in Pakistan we have
areas where wind is feasible and the bedrock or geology is shale based. Large
wind turbines are getting larger and therefore require a large pylon to support
the machine. This requires to pile-drive a massive steel beams into the
bedrock. The problem is that the bedrock may be made of shale and is known to
contain uranium and arsenic. Vibration from the pile-driving breaks up this
toxic shale below the groundwater and contaminates it. Area residents can’t
drink, bathe, or wash their clothes because of this. Water wells are being
poisoned . Construction of wind turbines
continues even though scientific tests at several farms show that well water
has been contaminated.
Canadian users of ground
water, attribute contamination of ground water to the wind
turbines being built nearby and the companies developing them. A large number of local rural residents who
believe the problems with their well water owe to the interaction between local
wind farm development and the area’s unique geology. The sedimentary bedrock —
dark in color and fine-grained — lurks beneath most of Chatham-Kent. It’s known
to contain sulphur, carbon, and toxic heavy metals. A resident says that his
well was drilled by his father half a century ago and had always run clear —
until sediment clogged it last October. Now, the water is the color of tea and
when poured and small particles sink to the bottom of a glass.
Ensuing government research debunked some of
the claims. A 2014 health federal health study, for instance, showed that “annoyance” was the
sole condition found to increase as levels of wind turbine noise increased.
(The report did note that community annoyance was statistically related to
health effects such as migraines, blood pressure changes, tinnitus, and
stress.). But events in Chatham-Kent raise the possibility that the massive
wind catchers pose unique and under-considered risks to the region’s
environment, and the health and safety of its residents.
Spokesman for Water Wells First and an area
farmer says the concern is that vibrations — either from pile driving
during the construction phase or, eventually, the everyday operations of the
turbines — might disturb the fragile Kettle Point black shale bedrock and
contaminate the ancient aquifer that serves as the local source of well water.
The worry was justified: It is well established that vibrations from pile driving can damage nearby
structures. As for ordinary turbine operations, one recent Canadian study
found a relationship between the vibrations and ground material within 100
meters of the structure.
Moreover, Water Wells First contends that the
company and ministry didn’t take the special characteristics of the local
geology into account. Residents realized their worst fears as the project began
the construction phase last summer. Nineteen wells began to experience sediment
problems, nearly a third of the 64 wells that the group members had tested at
their own expense. Bill Clarke, a hydro geologist for Water Wells First who
gathered and analyzed the samples, says follow-up testing showed the affected
wells experienced changes in water turbidity, amount of particles, color, and
rate of flow. While he says some of the changes were marginal, others were
alarming. In one instance, the black shale particle count jumped from 47
particles per milliliter to 681,939 — with nearly half of the particles being
as tiny as those found in cigarette smoke.
Tiny particles are potentially dangerous
because they can be too small to settle to the bottom of a well, nor can they
be controlled using conventional water filtration systems. A medical geologist
based in Ingersoll, says the acidic atmosphere in the stomach can break down
the binding between a clay-based shale particle and any heavy metals attached,
allowing the metals to settle in other areas of the body rather than to pass
through our digestive system
Wade
said turbines can be retrofitted to dampen vibrations and alternative anchoring
systems are available, but those would cost more. The water table is fragile in
Dover, part of a geological area stretching from Lake Huron to Chatham-Kent.
There are just 50 to 70 feet of overburden in most places covering black shale
bedrock.
Jakubec
and Stainton said there are studies from Scotland and Italy that have
identified seismic coupling. Jakubec, a green energy researcher, said impacts
tend to be felt from 1.5 to five kilometers away from turbine locations. Geological
engineer Maurice Dusseault wasn’t surprised to hear that Chatham-Kent water
wells were contaminated in the wake of pile driving for wind turbines.“Pile
driving emits a lot of low-frequency energy, and it is not at all surprising to
me that there could be related groundwater effects. The concept of
large-amplitude, low frequency excitation as an aid to liquid flow is reasonably
well-known,” the University of Waterloo professor said. “Low frequency
deformation waves are absolutely known to lead to fluctuation in ground water
levels as well as changes in the particulate count in shallow groundwater
wells.”
In
addition, Dusseault said affected residents were well-advised in having their
wells baseline tested prior to construction last summer. It’s the type of
evaluation he recommends. Before and after tests sent by the Water Wells First
citizens’ group to RTI Laboratories in Michigan show an exponential increase
[in] turbidity among the 14 affected wells, including [a] large proportion that
can be attributed to Kettle [Point] black shale particles
that are known to contain heavy metals, including uranium, arsenic and lead.
That’s
not the conclusion reached by the Ministry of the Environment and Climate
Change, as outlined in letters recently sent to affected well owners living
near the North Kent One project in the northern part of the Municipality of
Chatham-Kent. Whilst there’s been an admission that wells have indeed been
contaminated. That contamination can
only be attributed to “unidentified factors.” Pile-driving activities
associated with wind turbine development are not to blame, the MOECC maintains.
The
MOECC, in coming to its conclusion, relied upon the vibration evaluations
prepared for the developers Samsung and Pattern Energy, by Golder Associates
Limited. Golder measured changes to particle velocity as a measure of vibration
intensity created by pile driving.
The concerns have been dismissed by Chatham-Kent’s Medical Officer
of Health who concluded that there is no health risk from undisclosed particles
in water when no bacteria are present. Jakubec, however, said there are at
least two potential pathways through which the heavy metals in black shale
particles can enter the human body.
The issue is discussed, in detail, at: https://javedrashid.blogspot.com/2018/08/impact-of-wind-turbine-vibrations-on.html
Environmental impacts of Wind Energy
Despite its vast wind potential and benefits,
there are a variety of environmental impacts associated with wind power
generation that should be recognized and mitigated.
Land Use
The land use impact of
wind power facilities varies substantially depending on the site: wind turbines
placed in flat areas typically use more land than those located in hilly areas.
However, wind turbines do not occupy all of this land; they must be spaced
approximately 5 to 10 rotor diameters apart (a rotor diameter is the diameter
of the wind turbine blades). Thus, the turbines themselves and the surrounding
infrastructure (including roads and transmission lines) occupy a small portion
of the total area of a wind facility.
A survey by the
National Renewable Energy Laboratory of large wind facilities in the United
States found that they use between 30 and 141 acres per megawatt of power
output capacity (a typical new utility-scale wind turbine is about 2
megawatts). However, less than 1 acre per megawatt is disturbed permanently and
less than 3.5 acres per megawatt are disturbed temporarily during construction.
The remainder of the land can be used for a variety of other productive
purposes, including livestock grazing, agriculture, highways, and hiking trails
. Alternatively, wind facilities can be sited on brownfields (abandoned or
underused industrial land) or other commercial and industrial locations, which
significantly reduces concerns about land use
(Hybrid solar and wind farms save land and have other benefits, read more at https://javedrashid.blogspot.com/2018/10/hybrid-solar-wind-power-plants.html)
Offshore wind facilities require larger amounts of space because
the turbines and blades are bigger than their land-based counterparts.
Depending on their location, such offshore installations may compete with a
variety of other ocean activities, such as fishing, recreational activities,
sand and gravel extraction, oil and gas extraction, navigation, and
aquaculture. Employing best practices in planning and siting can help minimize
potential land use impacts of offshore and land-based wind projects
Wildlife and Habitat
The impact of wind turbines on
wildlife, most notably on birds and bats, has been widely document and studied.
A recent National Wind Coordinating Committee (NWCC) review of peer-reviewed
research found evidence of bird and bat deaths from collisions with wind
turbines and due to changes in air pressure caused by the spinning turbines, as
well as from habitat disruption. The NWCC concluded that these impacts are
relatively low and do not pose a threat to species populations
Additionally, research into wildlife
behavior and advances in wind turbine technology have helped to reduce bird and
bat deaths. For example, wildlife biologists have found that bats are most
active when wind speeds are low. Using this information, the Bats and Wind
Energy Cooperative concluded that keeping wind turbines motionless during times
of low wind speeds could reduce bat deaths by more than half without
significantly affecting power production. Other wildlife impacts can be
mitigated through better siting of wind turbines. The U.S. Fish and Wildlife
Services has played a leadership role in this effort by convening an advisory
group including representatives from industry, state and tribal governments,
and nonprofit organizations that made comprehensive recommendations on appropriate
wind farm siting and best management practices
Offshore wind turbines can have similar
impacts on marine birds, but as with onshore wind turbines, the bird deaths
associated with offshore wind are minimal. Wind farms located offshore will
also impact fish and other marine wildlife. Some studies suggest that turbines
may actually increase fish populations by acting as artificial reefs. The
impact will vary from site to site, and therefore proper research and
monitoring systems are needed for each offshore wind facility
Public Health and
Community
Sound and visual impact are the two
main public health and community concerns associated with operating wind
turbines. Most of the sound generated by wind turbines is aerodynamic, caused
by the movement of turbine blades through the air. There is also mechanical
sound generated by the turbine itself. Overall sound levels depend on turbine
design and wind speed.
Some people living close to wind
facilities have complained about sound and vibration issues, but industry and
government-sponsored studies in Canada and Australia have found that these
issues do not adversely impact public health . However, it is important for
wind turbine developers to take these community concerns seriously by following
“good neighbor” best practices for siting turbines and initiating open dialogue
with affected community members. Additionally, technological advances, such as
minimizing blade surface imperfections and using sound-absorbent materials can
reduce wind turbine noise .
Under certain lighting conditions,
wind turbines can create an effect known as shadow flicker. This annoyance can
be minimized with careful siting, planting trees or installing window awnings,
or curtailing wind turbine operations when certain lighting conditions exist .
The Federal Aviation Administration
(FAA) requires that large wind turbines, like all structures over 200 feet
high, have white or red lights for aviation safety. However, the FAA recently
determined that as long as there are no gaps in lighting greater than a
half-mile, it is not necessary to light each tower in a multi-turbine wind
project. Daytime lighting is unnecessary as long as the turbines are painted
white.
When it comes to aesthetics, wind turbines can
elicit strong reactions. To some people, they are graceful sculptures; to
others, they are eyesores that compromise the natural landscape. Whether a
community is willing to accept an altered skyline in return for cleaner power
should be decided in an open public dialogue.
Life-Cycle Global Warming
Emissions
While there are no global warming emissions
associated with operating wind turbines, there are emissions associated with
other stages of a wind turbine’s life-cycle, including materials production,
materials transportation, on-site construction and assembly, operation and
maintenance, and decommissioning and dismantlement.
Estimates of total global warming
emissions depend on a number of factors, including wind speed, percent of time
the wind is blowing, and the material composition of the wind turbine . Most
estimates of wind turbine life-cycle global warming emissions are between 0.02
and 0.04 pounds of carbon dioxide equivalent per kilowatt-hour. To put this
into context, estimates of life-cycle global warming emissions for natural gas
generated electricity are between 0.6 and 2 pounds of carbon dioxide equivalent
per kilowatt-hour and estimates for coal-generated electricity are 1.4 and 3.6
pounds of carbon dioxide equivalent per kilowatt-hour.
Environmental Impacts of Solar
Energy
The potential environmental impacts associated with solar
power are : land use ; habitat
loss; water use; and the use of hazardous materials in manufacturing , these
can vary greatly depending on the technology, which includes two broad
categories: photovoltaic (PV) solar
cells or concentrating solar
thermal plants The scale of the system — ranging from small, distributed rooftop PV
arrays to large utility-scale PV and CSP projects — also plays a significant
role in the level of environmental impact.
Land Use
Depending
on their location, larger utility-scale solar facilities can raise concerns
about land degradation and habitat loss. Total land area requirements vary
depending on the technology, the topography of the site, and the intensity of
the solar resource. Estimates for utility-scale PV systems range from 3.5 to 10
acres per megawatt, while estimates for CSP facilities are between 4 and 16.5
acres per megawatt.
Unlike wind facilities, there is
less opportunity for solar projects to share land with agricultural uses.
However, land impacts from utility-scale solar systems can be minimized by
siting them at lower-quality locations such as brownfields, abandoned mining
land, or existing transportation and transmission corridors. Smaller scale solar
PV arrays, which can be built on homes or commercial buildings, also have
minimal land use impact.
Water Use
Solar PV cells do not use water for
generating electricity. However, as in all manufacturing processes, some water
is used to manufacture solar PV components. Concentrating
solar thermal plants (CSP), like all thermal electric plants, require water for
cooling. Water use depends on the plant design, plant location, and the type of
cooling system.
CSP plants that use
wet-recirculating technology with cooling towers withdraw between 600 and 650
gallons of water per megawatt-hour of electricity produced. CSP plants with
once-through cooling technology have higher levels of water withdrawal, but
lower total water consumption (because water is not lost as steam). Dry-cooling
technology can reduce water use at CSP plants by approximately 90 percent .
However, the tradeoffs to these water savings are higher costs and lower
efficiencies. In addition, dry-cooling technology is significantly less effective
at temperatures above 100 degrees Fahrenheit.
Many of the regions in the World that
have the highest potential for solar energy also tend to be those with the
driest climates, so careful consideration of these water tradeoffs is essential
Hazardous Materials
The PV cell
manufacturing process includes a number of hazardous materials, most of which
are used to clean and purify the semiconductor surface. These chemicals,
similar to those used in the general semiconductor industry, include
hydrochloric acid, sulfuric acid, nitric acid, hydrogen fluoride,
1,1,1-trichloroethane, and acetone. The amount and type of chemicals used
depends on the type of cell, the amount of cleaning that is needed, and the
size of silicon wafer. Workers also face risks associated with inhaling silicon
dust.
Thin-film PV cells
contain a number of more toxic materials than those used in traditional silicon
photovoltaic cells, including gallium arsenide,
copper-indium-gallium-diselenide, and cadmium-telluride. If not handled and disposed
of properly, these materials could pose serious environmental or public health
threats. However, manufacturers have a strong financial incentive to ensure
that these highly valuable and often rare materials are recycled rather than
thrown away.
Life-Cycle Global Warming
Emissions
While
there are no global warming emissions associated with generating electricity
from solar energy, there are emissions associated with other stages of the
solar life-cycle, including manufacturing, materials transportation,
installation, maintenance, and decommissioning and dismantlement. Most
estimates of life-cycle emissions for photovoltaic systems are between 0.07 and
0.18 pounds of carbon dioxide equivalent per kilowatt-hour.
Most estimates for
concentrating solar power range from 0.08 to 0.2 pounds of carbon dioxide
equivalent per kilowatt-hour. In both cases, this is far less than the
lifecycle emission rates for natural gas (0.6-2 lbs of CO2E/kWh) and coal
(1.4-3.6 lbs of CO2E/kWh)
Agriculture
and Solar Cells; Jan., 23, 2020: It’s increasingly been suggested
that solar panels could be used on agricultural fields, producing clean
electricity while maintaining agricultural fields. Mint plants have been analyzed
after having grown on contaminated soil samples. Image credits: Fujian
Agriculture and Forestry University.
Perovskite cells have become some of the most efficient and
productive types of solar cells. Their efficiency can be well over 20% (long
considered to be a landmark in solar energy),
and they can be built from relatively low-cost materials — which means that in
the long run, the produced electricity can be quite cheap. They’re also the fastest-advancing
solar technology, raising even more hopes about their potential.. But
there are some issues to be considered, especially when it comes to lead. The
most commonly studied perovskite absorber is something called methylammonium
lead trihalide — a fiendishly complex substance which can leak lead into the
environment. In fact, all perovskite cells contain methylammonium ions
surrounded by heavy metal atoms. Most commonly, these metal atoms are lead. If
some of this lead does reach the ground, researchers found, it can be easily
absorbed by plants — even more easily easier than lead from other sources.
To test this, Prof. Antonio Abate at the Helmholtz-Zentrum Berlin
and colleagues from Germany, Italy, and China, set up an experimental design.
They contaminated soil samples with lead from either perovskite solar cells or
other lead sources and then cultivated different plants (mint, chili, and
cabbage). After allowing the plants to grow and develop naturally, they
analyzed how much lead could be found in the plant body and leaf.
Surprisingly, the lead from perovskites was 10 times more
bioavailable than other sources of lead contamination — so if any perovskite
lead reaches the soil, it is very likely to be accumulated in plants. Similar
trends were observed when the lead was replaced with tin.
Needless to say, lead is toxic and should not reach the food chain
in any form. But the scale of the problem also warrants some clarification. A
square meter perovskite solar module contains a total of only 0.8 grams of lead
— which is very little compared to other technical sources of lead, such as
batteries. Furthermore, it’s unlikely
that all the lead content would leak into the environment. Nevertheless, it’s a
problem that warrants further investigation, says Professor Christos Markides,
Head of the Clean Energy Processes at Imperial College London, who was not
involved with the study.
“This is an interesting study concerning the environmental
impact of lead in perovskite solar cells, a photovoltaic technology that has
attracted significant attention recently owing to its excellent performance and
promise of lower cost compared to conventional and other alternatives. It is of
note because it explores the impact on plants of the use of lead in such solar
cells and provides evidence that this is something that should be considered
with great care,” Markides explains.
“Concerns relating to the
widespread deployment of lead-based perovskite solar cells have been raised for
some time, given that these toxic materials are soluble in water, so
contamination can lead to environmental but also health issues once they enter
the food chain.”
In addition, there are important limitations to this study. We
don’t really know how much lead actually leaks from these cells, and how it is
absorbed by plants — particularly plants other than the ones trialed here. So
this study shouldn’t be interpreted as “solar panels leak a lot of lead into
plants”.
Andrew Meharg, Professor of Biology at Queen’s University Belfast,
also highlighted the study’s limitations: while this does pinpoint a reason for
further study to better understand the leakage and absorption of perovskite
lead, it is very unlikely that this poses a major environmental problem.
“Lead contamination of soils is multiple and extensive, and in
cases extreme, globally, from a wide range of industrial and domestic
activities, yet lead in crops is not really a concern due to lead’s poor
mobility in soils, its limited uptake by and restricted translocation within
plants.”
“The lead from the
peroskovite lead is only 0.1% of panels, and only doubles in the edible parts
(leaves) of one plant (mint), tested on one soil. The break-up and leaching
scenarios to soils of solar panels needs investigated, this was not conducted
here, To state that all lead in solar panels should be replaced, with another
toxic and problematic element tin, from such limited findings is not warranted
without further extensive testing in a range of actual soils that have been
contaminated in situ by disused solar panels.”
https://www.zmescience.com/science/solar-panels-lead-plants-21012020/
Drawbacks of VRE: Jun., 12, 2020: The film starts by
highlighting the primary limitation of wind and solar power: They’re weather
dependent and sometimes produce no electricity. Consequently, these
intermittent sources need to be backed up by something more reliable, and, as
the filmmakers found, those reliable electricity sources are often fossil
fuels. In addition to sometimes not showing up for work, wind and solar plants
require nearly 100 times more land to generate the same
amount of electricity as a natural gas plant. The film
illustrates this in detail, showing a football-field-sized solar array only
capable of powering just 10 homes in a Michigan town. At one point, the site
developer notes that to power the whole town, it would take a solar array so
large it would require 15-square miles.
The
alternative to relying on fossil fuels for backup is large-scale lithium
battery storage. The film notes, however, that these batteries are prohibitively
expensive, and the current world supply of energy battery storage
can hold just one tenth of one percent of global energy usage.
These
obstacles are enough that, after several decades and half a trillion dollars of
investment
(even more globally), wind and solar combined generate just 9 percentof
America’s electricity and less than 4
percent of its energy.
But even
these challenges deal only with fully functional green technologies. The film
shows that creating wind turbines, solar panels and batteries relies on a mining and
manufacturing process so intensive that one wonders if saving the
planet really is the goal. The production of each of these technologies depends
on the very fossil fuels they’re attempting to replace and creates
indispensable toxic waste in the process. The film also notes the frequent
large-scale habitat
destruction that accompanies green energy installations,
underscoring the inescapable fact that every energy
source has an environmental impact.
Further,
wind turbines and solar panels have lifespans of roughly 20 years, which means
this process must be repeated. This lifespan is less than half the lifespan of
any traditional plant, adding to the land use disparity. For instance, natural
gas plants can last
40 years, and nuclear plants between
60-80 years.
All
these challenges underscore the point made by environmental scholar Richard
York interviewed in the film: Contrary to popular belief, green energy does a poor job displacing fossil
fuels. It takes “between four and thirteen units of non-fossil energy to displace
one unit of fossil energy.”
This
isn’t to say, though, that the pursuit of green energy is futile. When used in
moderation, wind and solar power can relieve pressure on the grid by providing
low-cost electricity. As the film notes, however, problems arise when green
energy integration is stretched beyond its
useful limits. It doesn’t matter how cheap green energy gets if it
can’t provide electricity when you need it.
While
the film indulges in overpopulation
theories and anti-capitalist rhetoric typical of Moore’s films, it nonetheless
is an important contribution to the green energy discussion. The general public
has largely been shielded from green energy’s intermittency, scale, land use
and lifespan barriers that energy analysts have written about for years. By
introducing these matters to a wider audience, Moore has reminded us that while
green energy certainly has its place, it also has its limits.
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