Today America and the world as a whole are approaching a set of problems that we all will inevitably have to deal with. We have an overpowering addiction to energy and most of that energy we currently use comes with many problems. The United States has, for a long time, enjoyed some of the cheapest and most abundantly available energy. Some figures show that a typical household of three in the United States averages a consumption of 6,000 kilowatt hours (kWh) of energy per year (Silverman, 2007). Fossil fuels, such as coal, natural gas and oil, make up the majority of what we rely on. In 2011, fossil fuels provided 87% of the world’s energy (“Renewable energy —," 09). Fossil fuel supplies around the world are dwindling as demand is increasing (US Senate, 2010). It is estimated that there are 10,800,000 terawatts (TW) of nonrenewable energy (nuclear and fossil fuels) left in the world today (Brenner Information Group, 01). As our fossil fuel supplies dwindle and we are forced to increasingly look overseas for further supplies, and especially as their supplies dwindle, we can expect two things to happen; costs are going to skyrocket and we are going to see dramatic increases in risks to our national security and economy (US Senate, 2010). Even worse are the major contributions to global warming. For every 1 kWh of electricity produced from fossil fuel plants, there are 1.2 to 1.4 pounds of CO2 added to the atmosphere (Brenner Information Group, 01). Just this month some very sad news hit headlines, including National Geographic:
Climate Milestone: Earth’s CO2 Level Passes 400 ppm, Greenhouse gas highest since the Pliocene, when sea levels were higher and the Earth was warmer.
America’s current reliance on oil poses significant economic and national security obstacles for us today and they are only expected to get worse (US Senate, 2010). Oil also endangers our environment through the steps that we must take in collecting it, transporting it, refining it and even in its use. Today, the Gulf Coast is still dealing with the negative impacts of the BP Oil Spill. For every mile of oil pipelines we build we escalate the likelihood of another major tragedy.
Coal is cheap and domestically available, but has many of the same environmental hazards, plus the hazards faced by the miners who mine it. There is really no such thing as “Clean Coal” and there are many unintended consequences that come with the mining of coal.
Natural gas is plentiful and cleaner than oil or coal, but it still has environmental hazards and, as its use is becoming more popular, the efforts to collect it are raising new concerns in the environmental sense. Fracking will inevitably infiltrate our drinking water with the fracking chemicals and other contaminates from the ground. There are also national security implications with natural gas and there is evidence that switching to natural gas would provide the United States with the same, if not worse, situation as we have with oil (US Senate, 2010). Iran is actually a large holder of natural gas reserves, as well as other nations with similar relationships with the United States. If we end up invading Iran, it would be interesting to see how quick we move to “secure” the areas with high natural gas concentrations. This could likely be a repeat of the Iraq quagmire.
With the numerous fossil fuel issues mentioned¸ as well as the ever growing problem of global climate change from accumulating greenhouse gases, leaders around the world are reevaluating their energy supplies and are looking for better options. Nuclear power is what comes to mind first, this is a cleaner method of energy, as far as greenhouse gases.
The complications that come with storing the spent fuel and dealing with the contamination from accidents, which can take around one-thousand years to become harmless, finally leads the discussion to renewable resources (World Nuclear Association, 2011).
Renewable Energy Sources
Renewable energy sources are not perfect and there are opponents to these options for various reasons. One major complaint about renewable sources is that they aren’t growing fast enough and don’t produce enough energy, merely supporting the more common sources (“Renewable energy —," 09). A big reason for this problem is that developing nations automatically go for the cheap energy sources, which are typically fossil fuels, this keeps demand for alternative sources low which limits investment in growing the renewable energy industry (Renewable energy —," 09). Along with the higher cost for energy from renewable sources, another major objection is that they rely on an intermittent nature, with unpredictable loss of wind and nightly loss of sunlight. Following that argument, many say renewable energy plants are typically too expensive to build and have complicated needs that need to be addressed when deciding where they can be built (“The advantages and,"; “Disadvantages of Renewable," 2011).
Current Actions with Renewable Energy Sources
United States investment in renewable energy reached more than $28billion, while venture capital and private equity investment reached $2.7billion, according to the 2010 Renewable Energy Data Book released in 2011 by the United States Department of Energy. In the United States 25% of all new electrical capacity installations in 2010 were renewable energy (2010 renewable energy," 2011). Over the prior decade, the growth rate for nearly every class of renewable energy dramatically exceeded those of fossil fuels and nuclear power. However, renewable sources are coming from the back of the pack and may have some difficulty becoming a major part of our supply (“Renewable energy —," 09).
Comparison to Other Nations Policies
Even with the improvements the United States has been making, there is still room, and a pressing need, to take more aggressive action towards renewables. Other nations have taken a far more proactive role and are, seemingly, decades ahead of us. Iceland is planning to be 100% fossil fuel free in the near future, as they’ve utilized their geothermal resources to produce over 26% of their energy needs and to heat 87% of homes (“Our energy," 2007). Germans can earn cash for their efficiency coupled with using wind turbines and solar panels, as anything they produce above their needs goes in to the grid to be shared, resulting in a personal profit for their contribution. Many Germans have even rented neighbors’ roofs to install additional solar panels and gain further income (Brenner Information Group, 01). Unfortunately, there are stories of failure as well in the global populations; around 25% live without electricity, which serves to keep them in poverty (Brenner Information Group, 01).
The most commonly used renewable resource in the United States is hydro-electricity, typically generated by turbines built in to dams on rivers. Hydro-electric energy in the United States produces enough energy to support 28.3million people (“Renewable energy: facts," 2011). Hydro-electric power has been increasingly regrettable, though, as its unanticipated impact on rivers has caused many negative consequences for both nature and people’s livelihoods (U.S. Department of Energy, 2006). For that reason I would like to focus on the renewable energy sources of wind, solar, geothermal and tidal. Renewable energy sources, excluding hydro-electric, in the United States reached a production of 59GW in 2010 (“2010 renewable energy," 2011). All of these sources have been gaining more popularity and interest recently as we work towards finding solutions for our energy dilemmas.
Wind energy is as simple as it sounds. It is essentially the complete opposite of a fan. Where a fan consumes electricity to rotate blades which propel air, a wind turbine catches the wind which causes the blades to propel and rotate the attached turbine which produces electricity. Wind turbines come in a variety of sizes and types and can be used privately for a residence or be part of a wind farm that contains several large wind turbines and produces energy to be shared within a power grid (US Department of Energy, 2011).
Wind energy is one of the most discussed options currently, but these discussions have contained some stern criticism for wind energy. Complaints have been repeatedly made in regards to the low level noise that occurs from the rotation of the turbines, some cases of animals being affected by this noise on farms has also been reported. Many also complain that the enormous wind turbines pose an eyesore on the natural scenery and potentially pose a risk to property values because of that. Also a source of discontent is that wind turbines and their access roads use large amounts of land, this is especially so when poor planning takes place. Wind is also the most unpredictable of sources. Should a grid rely on wind for a large portion of its demands, that grid could easily be overloaded when the wind stops (“Disadvantages of Renewable," 2011). A new concern about wind farms was discovered at Travis Air Force Base in 2006. During air traffic radar transitions, the radars displayed inaccurate images. Weather cells were appearing without actually being present, and aircraft tracks kept disappearing and reappearing. This odd incident was attributed to a wind farm of over 700 wind turbines that lies southeast of the base (Collick & Losco, 2012). Questions have resulted from the Travis Air Force Base incident as to what other impacts wind turbines could have on aircraft safety.
Despite its critics, wind energy has a great deal to contribute. Wind energy is one of the fastest growing sources worldwide, globally increasing by a factor of eleven and by a factor of 16 in the United States during the last decade (“2010 renewable energy," 2011). There are already very large wind farms around the world. The offshore wind farm, Horns Rev 2 Farm in Denmark, was completed in 2009 and has a capacity of 209MW. The Roscoe Wind Farm in west Texas has a capacity of 782MW and was completed in 2009. China is currently developing a wind corridor in the Gansu Province that has 20,000MW as its ultimate goal (“World's largest renewable," 2011). On average, 14mph is needed to produce electricity, with that, up to 300 homes can be supported by a single turbine (“Renewable energy: facts," 2011). Today, wind turbines are being manufactured ever more efficient and with models that can be utilized in a wide variety of needs. With the continued expansion of wind energy, we can only expect to see greater developments that allow larger and larger capacities to be available without CO2 emissions.
Every bit as major as wind energy is solar power. Solar energy is the product of converting sun light to electricity. This can be done in more than one way. One is done with photovoltaic (PV) cells. These cells are made of various materials and when the sun strikes them an electron is released from its host atom and passes through a special membrane that doesn’t allow it to pass back. This causes a negative charge on the surface and a positive charge on the opposite side. These surfaces are connected through a circuit to accept the charges for electricity (Brenner Information Group, 01). Another type of solar energy is called concentrating solar power (CSP). This produces energy by using mirrors to focus sun light on special receivers that convert it to heat. The heat is used to produce steam and that steam is used to turn a turbine ("U.S. department of energy," 2011). Solar energy has a vast variety of uses from large solar farms to personal use for the tiniest of electronics, such as a wrist watch (U.S. Department of energy, 2011).
Solar energy is not without its critics either. Solar energy is viewed as inefficient because only 12% to 18% of solar energy is converted to electricity by silicon in solar panels (Brenner Information Group, 01). Even environmentalists have joined others in posing concerns about toxic metals, including lead, mercury and cadmium, utilized in producing solar panels and even argue that CO2 is also produced in the process (American Chemical Society, 2008). As mentioned before, cost is another large factor and a solar plant can cost between $3.5million and $6million to build, surpassing the cost of other traditional types of power plants (“Disadvantages of Renewable," 2011). The, afore mentioned, inconsistency of solar availability as a source is also of primary concern.
Solar energy is probably the easiest energy source to establish for small scale use. The size of the equipment makes it quite simple to find a location for, as far as private use. Though panels may only be able to convert 12% to 18% of the sun’s energy, their flexibility with size and placement locations allows for the easy inclusion of more panels to meet need (Brenner Information Group, 01). Experts explain that for home use one needs to view purchasing solar panels as an investment in the future (Brenner Information Group, 01). The long term payoff, typically from 5% to 15%, is what makes it worth it (Brenner Information Group, 01). According to Brenner Information Group, “A typical home appreciates 50% - 75% of the solar system cost. Another study estimates that your home appreciates $10 - $25 for each $1 reduction in your annual electrical bill.” Solar systems cost between $5 and $8 per watt of energy produced. The payoff typically comes in 9 to 15 years after it is installed. The most common use for home solar systems is what is called “peak shaving” (Brenner Information Group, 01). This is essentially having the solar system supplement the overall energy need to reduce the amount of energy coming from the utility company during the day, when rates are higher (Brenner Information Group, 01). Another version of “peak shaving” is similarly using the solar energy to supplement needs but to keep the amount used from the utility company within the lowest tier of usage, where the rates are lower, and out of tier 3, where rates can be 300% more (Brenner Information Group, 01). Residential solar systems are typically about 83% to 85% efficient (Brenner Information Group, 01). As mentioned earlier in reference to Germany, some power grids are set up so that a home owner can benefit from providing unused energy to the grid, this is called net metering, at the end of the year the home owner’s usage and contribution are reconciled (Brenner Information Group, 01).
Another benefit of solar is that it uses materials that are plentiful and it has a very minimal impact on the environment (Blakers, 2008). The PV market is reported to be doubling every 20 months since 2000, according to an article by Professor Andrew Blakers in Science Alert, and this is reducing the cost. In the same article, Blakers explains that “only about 0.3% of the world’s land area would be required to supply all of the world’s energy requirements. The area of roof is sufficient to provide all of Australia’s electricity, using PV panels.” Blakers takes on those who are clinging to nuclear or fossil fuels, explaining that “Gram for gram, advanced silicon solar cells produce the same amount of electricity over their lifetime as nuclear fuel rods. Per tonne of mined material, solar and wind energy systems have 100-fold better lifetime energy yield than either nuclear or fossil energy systems.” Solar has already been performing well in other parts of the world; Australia uses 30,000 times more solar energy each year than they do from all their fossil fuels (Blakers, 2008). There are several large scale solar plants in the world today and more being considered all the time. In 2008, Spain completed the Olmedilla Photovoltaic Park with a capacity of 60MW (“World's largest renewable," 2011). Here in the United States, in the Mojave Desert of California, the Solar Energy Generating Systems plant was completed in 1990 and has a capacity of 354MW (“World's largest renewable," 2011). The Chinese currently have plans for a 2,000MW plant in the Mongolian Desert, no planed date of completion is available at this time (“World's largest renewable," 2011).
At UCLA, researchers have come up with something new that could open up options for many large commercial buildings. This type of polymer solar cell that they’ve come up with produces energy while being at least semitransparent (Transparent solar cells, 2012). Transparent, or even semitransparent, cells could allow windows to generate power. Instead of paying to tint windows to limit the sun or frost them to obtain privacy, semitransparent solar cells may, in the near future, be able to fill that task and reduce energy consumption from the utility company. Other developments showcased by ACS showed breakthroughs that would allow for use of more common materials to even be used to produce panels ("New solar panels," 2012). There is even hope on the horizon for sidewalks and roads to be used as solar energy surfaces. One company has been doing work that could create highways that pay for themselves by collecting solar energy because they will be constructed of solar panels("Solar roadways: A," 2013). Imagine being a business or community and using roads, sidewalks and parking lots to draw energy and revenue from the collected energy. According to the Brenner Information Group, there are 350,000,000TW of energy sent to earth from 15 minutes of full sun. In less than 5 years, we can expect nano-engineered solar panels that are expected to bring the unit cost of energy from solar down to the level of fossil fuels (Brenner Information Group, 01).
As mentioned with Iceland’s energy sources, geothermal is also a source of consideration for renewable energy sources. Geothermal Energy production is done a variety of ways; however, they all involve utilizing the virtually inexhaustible heat from the earth. One of the ways that geothermal energy is utilized is by using hot springs or geysers to obtain steam which turns a turbine to generate electricity. Another method utilizes hot spots on the earth where magma is near the surface and external water sources are used to generate the steam that turns the turbine generating electricity ("Geothermal technology program," 2012).
The problem with geothermal power is that it calls for a great deal of patience. New techniques and technologies are slow coming and full of setbacks. To even establish a geothermal energy field, it can take 5-7 years to go through the steps of obtaining permits and financing then finally drilling (“Disadvantages of Renewable," 2011). Perhaps this is why financing is so difficult to come by, making it near impossible for small developers to get the needed backing. There are also immense regulations that must be addressed in trying to establish a geothermal energy field. This makes the already complicated process of finding a location, with favorable characteristics for generating power, even more difficult (“Disadvantages of Renewable," 2011).
Geothermal can compete readily with fossil fuels in the arena of cost, however. New plants can generate energy for about $0.04 to $0.07 per kWh and the total resources of geothermal surpass that of all nonrenewable sources combined (“Our energy," 2007). The 2012 Annual Energy Outlook, issued by the United States Energy Information Administration, estimates for electric plants entering service in 2017 that the levelized per MWh cost for geothermal energy will at least be even, if not cheaper, than coal energy, comparable to the various types of natural gas energy and cheaper than nuclear energy. Geothermal plants do not typically require use of water, another precious resource. According to the Geothermal Energy Association, “Air cooled geothermal power plants do not consume any water. Geothermal plants that use water for cooling typically use geothermal water or steam condensate and not fresh water. Geothermal power plants could also produce potable water from geothermal condensate, and at least one such plant was designed recently for use in East Africa.” While some are critical of the potentially random locations that these plants could find as suitable homes, geothermal energy actually turns that in to a good thing. In many cases, a geothermal plant will have a positive impact on a rural area as it brings in revenue and new jobs (“Geothermal energy association,”). Geothermal plants do not require any fuel to be mined or shipped to the plant for it to operate. Causing no harm to the air, wildlife or land that hosts it, geothermal plants have one of the smallest ecological foot prints of any energy source (“Geothermal energy association,”). Geothermal energy is a great energy source as far as electricity, but it also can support our needs in other ways. It is common for geothermal heat at hot springs or geysers to be used to provide heat for homes and buildings, as well as acting as a hot water heater for those same people. However, geothermal energy can be used for home climate control and hot water heating in homes that are nowhere near hot springs or geysers. This is done with geothermal heat pumps (GHPs). The Geothermal Energy Association explains that,
“Geothermal heat pumps take advantage of the Earth’s relatively constant temperature at depths of about 10 ft. to 300 ft. GHPs circulate water or other liquids through pipes buried in a continuous loop, either horizontally or vertically, under a landscaped area, parking lot, or any number of areas around the building. To supply heat, the system pulls heat from the Earth through the loop and distributes it through a conventional duct system. For cooling, the process is reversed; the system extracts heat from the building and moves it back into the earth loop. It can also direct the heat to a hot water tank, providing another advantage — free hot water. GHPs reduce electricity use 30–60% compared with traditional heating and cooling systems, because the electricity which powers them is used only to collect, concentrate, and deliver heat, not to produce it.”
GHPs are recognized by the EPA as one of the most efficient heating and cooling systems (“Geothermal energy association,”). The National Renewable Energy Laboratory released a report in 2006 titled The Energy Under Our Feet, it provided estimates that by 2015 26,000MW of geothermal power could be developed with another 20,000MW from heat pumps. In the same report, predictions for 2025 give the possibility of exceeding 100,000MW of geothermal energy and an additional 70,000MW coming from heat pumps and direct use heating. In a 2012 article in Business Wire titled “GEA national geothermal summit to address challenges in advancing geothermal industry in California and beyond,” it was reported that 502.7MW of geothermal energy has been added through the construction of 28 geothermal plants or additions in nine states since 2006. The largest geothermal operation in existence is known as The Geysers in northern California. This plant has a capacity of 1,000MW and first began in 1921 ("World's largest renewable," 2011).
Tidal energy, as it sounds, utilizes the movements of the ocean to generate energy. There are numerous types of devices that can be used to collect the energy of ocean waves to create electricity. Some are as simple as underwater versions of wind turbines. Others use floating or submerged parts that work like buoys and move with the waves, which results in them pulling on a tether that attaches to a spool and turbine and functions much like a yo-yo. Another design captures water as it washes over the top edge of a reservoir and then allows the water to drain from the bottom where it turns a turbine. Yet another type uses a partially submerged device with a sealed air chamber in the top and an open collecting chamber in the bottom and a turbine in between them. As waves are collected in to the lower chamber and then released, a constant variation in the air pressure between the two chambers causes a back and forth motion of air through the turbine which produces electricity ("Marine and hydrokinetic," 2011). There are other types of devices for tidal energy, but these serve as an adequate example.
There are many problems with tidal energy. The United States Department of Energy estimates there are only about 40 places in the world that are capable of supporting tidal barrages, which are required for some of the devices. Tidal barrages are very similar to hydro-electric dams and require the same kind of capital investment and bring with them the same kinds of environmental impact on the rivers, just at a different part. They have also been known to have negative impacts on marine life in the area. The other devices that do not require tidal barrages are very new and have not had enough use for significant data to be available. Tidal energy projects also tend to be slow to develop and are frequently abandoned before completed. In many cases, the energy being generated is taking place far from where it is being consumed, which creates difficulty in bridging the gap between supply and demand. A costly down fall is when rough seas, brought on by severe weather, inflict serious damage to tidal energy systems, particularly those on the sea floor (“Disadvantages of Renewable," 2011).
Tides occur every day in a very consistent pattern, because of this tidal energy is more predictable than some other renewable energy forms. The cost of tidal energy depends entirely on where it is and where it needs to be supplied to (Habjanec, 2008). Tidal energy systems may have a high initial cost, but they are considered about 80% efficient and much of the structure built for the systems can be utilized as parts of bridges and roads (Habjanec, 2008). Tidal energy has only recently regained attention and will likely begin improving in the areas of cost and efficiency as it receives further efforts at development. Currently the largest tidal energy systems are the Agucadoura Wave Farm in Portugal, first installed in 2008, with a capacity of 2MW; and the Rance Tidal Power Station in Brittany, France that was completed in 1966 and has a capacity of 240MW ("World's largest renewable," 2011).
I believe the biggest problem that needs to be faced, before we can achieve a solution to this much larger problem, is the current state of discourse. Not unlike the discourse for most of our issues today, the discourse taking place is built on a foundation of uninformed and misinformed minds. People’s own selfish desires, both large and small, are driving attitudes that are determined to ignore information and reject potential changes, as well as create misinformation campaigns to draw support away from these solutions. This is further complicated by having excessive and drawn out decision making processes at various levels of various governments. A group of anthropologists looked at this dynamic and explained that there needs to be a national policy because the state level political discourse is unproductive and lacks direction producing, at best, a “patchwork” of different policies (Melnick, Rand & Stephens, 2009). I agree with this call for a national policy. I also believe there is going to have to be aggressive action to educate the public and neutralize the misinformation efforts out there. From that point, the steps towards a solution get more extreme and will call for some very strong leadership from our government.
I believe we need to place a priority on development and widespread use of wind energy, solar energy, geothermal energy and tidal energy at both commercial and personal levels. The government needs to be extremely difficult in allowing any new fossil fuel power plants to be built and needs to tax fossil fuel plants for the amount of fuel they are using. That still leaves the need to motivate people at the personal level as well. To get the people to choose change, two things have to take place. First, the thing that you want them to change to needs to look as appealing as possible. Second, the thing you want them to change from needs to become less appealing. I would like to see steep fossil fuel taxes implemented on all energy produced by fossil fuels. Those taxes would need to progressively increase, encouraging people to choose supplemental renewable energy improvements for their homes and businesses, yet giving them time to freely choose to do it. The revenue generated from these fossil fuel taxes should then be rolled in to government programs to assist and reward individuals and small businesses as they make the transition to fossil fuel free electricity.
At the same time, a government requirement needs to be implemented for all new vehicles sold in the United States to be Flex-fuel (ethanol or methanol) and hybrid with capability to charge the battery by plugging it in. Ethanol has caused problems economically and in regards to our food costs. In a 2010 Senate hearing, Gal Luft, the Executive Director of the Institute for the Analysis of Global Security and Co-Founder of Set America Free Coalition, testified in favor of methanol as an option, stating, “Methanol packs less energy per gallon and is more corrosive than ethanol. But it is cheaper and far easier to produce in bulk. While ethanol can be made only from agricultural products and biomass, such as corn and sugar cane, methanol can be made from agricultural waste, coal, industrial garbage, natural gas, and even carbon dioxide. Yes, in my view, this is perhaps the most promising way of dealing with our carbon dioxide problem, is turning it into methanol.” As far as our transportation is concerned, we should implement the fossil fuel taxes on petroleum based fuel, but implement them more conservatively until there are conversion kits available for older vehicles to become Flex-fuel. However, requiring annual inspections to ensure vehicles are operating within the California Emission Standards would also be a positive step. I believe by pressuring the auto-industry to develop conversion kits for older vehicles to become Flex-fuel could produce some reasonably fast results and keep the cost lower, due to the mass production that would be required, which would also likely involve the creation of new jobs.
To solve the problems of intermittent nature disrupting wind power and nights disrupting solar, we need to further develop a national power grid that allows for efficient sharing of power across the nation. As part of that grid, there needs to be the capability for everyone with personal solar and wind turbines to send their excess energy production back in to the grid and receive credit towards their bill. A further step to add reliability would be to implement pumped storage systems. These are essentially hydro-electric dams that act like batteries. During peak energy production, pumps move water in to giant reservoirs and when the sun goes down the water is released to flow over turbines to produce energy by hydro-electric means till solar is available again. This does not cause problems for any rivers or drinking water supplies because the quality of the water doesn’t matter. It could be sea water or even treated sewage that is pumped in to the reservoir to wait till we need it as an energy reserve ("Water power program:," 2011). This would create an incredibly stable and reliable source of energy with nonrenewable sources as a last resort back up. What is most important to remember, is that all of these technologies and devices will rapidly decline in price and increase in efficiency as they become increasingly in demand and are mass produced.
We have been addressing this very serious situation with an attitude much like a teenager who is putting off studying for a final exam. We know there is something very serious coming our way that we will have to do a great deal of work to address, but we continue to procrastinate and wait till later to prepare. We are running out of time and the action that needs to be taken is only going to get increasingly drastic.
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