The urgent need for renewable energy solutions mounts with each passing year; knowledge of the irreversible consequences of mankind’s growing carbon footprint are no longer confined to scientific circles. As a result, governments have become obliged to implement sustainability policies, particularly given the potential long-term economic repercussions of climate change.
Many countries around the world are attempting to implement more impactful environmental policies, whether that involves recycling programmes, creating the infrastructure for alternative energy resources, or reducing air pollution. There are those that stand out for their efforts, such as Iceland’s effective climate change policy and timber reserves management, or Sweden’s low carbon dioxide emissions and organic agricultural practices. Leading in terms of alternative energy and sheer political will to switch to clean electricity generation, however, is Costa Rica: a small Central American nation that currently finds itself the focus of the world’s environmental community.
For years, Costa Rica has held a strong reputation for safeguarding its unique biodiversity and its earnest efforts to protect the rainforest that covers much of the country. Following a period of intense deforestation during the 1960s (a result of cattle ranching and agricultural development), government legislation and the protection of over 50 percent of Costa Rica’s rainforests, as well as numerous National Parks, ensued and has since made it a pioneer for forest conservation in the region.
Year by which Costa Rica plans to run solely on clean energy
Of the country’s electricity came from hydropower in 2014
Of the country’s power comes from geothermal sources
“Costa Rica is a very interesting country and I really believe that they are at the forefront of Central and South America in terms of innovation and creativity and certainly in terms of environmental consciousness”, says Bruce Cutright, CEO of Texas-based geothermal energy company Thermal Energy Partners. Costa Rica’s progressive sustainable policies are not limited to conservation: through rigorous efforts by the government, the country has made strides in the field of renewable energy. According to the Green Energy Leaders report published by the World Wide Fund for Nature: “In the Latin American region, [Costa Rica] is the cleanest country in terms of a range of factors: energy consumption per unit of GDP; carbon intensity in energy conversion processes; impacts over air and water pollution related to energy production; and amount of emissions for electricity produced.” By 2021, the Costa Rican Institute of Electricity (Instituto Costarricense de Electricidad, ICE) aims to run the country solely on clean energy.
For the first three months of 2015, the entire country ran on sustainable energy resources, making Costa Rica the first nation in the world to fully utilise sustainable energy for such a stretch. This commendable achievement was made possible as a result of unusually heavy rainfall, which meant the national grid did not require fossil fuels to fulfil the state’s electricity needs. The ICE instead relied upon hydroelectricity generated by the country’s four reservoirs (Arenal, Cachi, La Angostura and Pirrís), which all surpassed the generation estimates for the first quarter of this year. Other renewable sources were also used to contribute electricity to the energy mix, including wind, biomass, solar and geothermal power, albeit not to the same degree.
Last year, 80 percent of the nation’s electricity requirements were produced by hydropower, showing much promise for the 2021 plan. “Costa Rica has a huge number of locations for hydroelectricity dams; they have a number of them operating right now”, says Cutright. Although damming rivers to tap into the hydroelectric power has its own environmental drawbacks, the energy that is then produced is completely clean. It is also easier to scale up than other alternative energy resources, such as solar and wind power, and can be run at all hours.
However, a major challenge of using hydroelectric power is its high degree of unpredictability. This was seen last year when a state of emergency was declared due to the drought experienced in the northwest region. The withdrawal from the electricity grid forced the ICE to switch to diesel generators. Cutright says: “Power that is generated from hydroelectric dams [is] based on statistical analysis of past river flows and rainfall events. As climate change has more of an impact, the predictability of rainfall and river flow decreases.”
There are around 100 active volcanoes on Costa Rica, making it a prime area for traditional geothermal development activities. Its capabilities in this area were first discovered in 1959 and then confirmed by a convoy of UN experts in 1963 and 1964. Following exploration activities in the Miravalles Geothermal Field, a plant with a 163.5 MW capacity was erected. Government efforts to further exploit the country’s geothermal resources then led to the construction of a binary power plant in the Las Pailas Geothermal Field, which began operations in 2011 with a capacity of 42.5MW. Feasibility studies for a second unit in the Las Pailas Geothermal Field are being conducted.
Geothermal energy has become a base load for the system, and now produces around 15 percent of Costa Rica’s total electrical power. It was after the country’s severe drought last year that the government and the ICE unveiled plans for a $958m geothermal energy plant in Guanacaste, near the northwestern province Rincón de la Vieja. By working towards a greater contribution to the energy mix from a more reliable source of renewable energy, Costa Rica can still progress towards its clean energy role, while bypassing the challenges presented by a dependence on hydroelectric power.
The project consists of three plants: the first will generate around 55MW at a cost of $333m. Two additional plants will then be built, and will have a capacity of 50MW. “If you lose one plant, you don’t lose a large capacity off the grid”, says Cutright. The project is being backed by the Japanese International Cooperation Agency, which is contributing a loan estimated at over $540m, while the European Investment Bank is providing around $70m.
The benefits of geothermal energy as a source of reliable and clean energy are abundant: it produces zero carbon emissions and its physical footprint is significantly smaller than other generating sources. Around 2.5 acres of land is needed for a 10MW geothermal plant, whereas almost 100 acres is required for a plant that can generate just one megawatt of solar power.
Wider, faster, longer
Over the last decade, there have been significant technological improvements to geothermal energy generation that have promoted its cost-effectiveness and made it more widely available. Major improvements have been made to the drilling technology, allowing geothermal wells to be sunk to greater depths and at less cost than was previously possible. Consequently, tapping into geothermal energy is no longer confined to the areas around hot springs and volcanoes.
“The deep drilling and well completion technologies that have been developed over the last decade in the petroleum industry, when applied to the geothermal industry, have made the production of geothermal energy competitive over a much larger geographic region”, explains Cutright.
The second major technological advancement in the field has been in the increased efficiency of thermal to electrical generation, specifically for binary and flash steam generators. These improvements in the binary cycles enable geothermal plants to be online approximately 97 percent of the time, making energy generation more accessible than even the best managed coal or nuclear plants.
“This is one of the clearest benefits of geothermal power production when compared to other renewable energy sources; geothermal energy is available 24 hours a day, 365 days a year”, says Cutright. “And with highly efficient generators, there is very little downtime for maintenance or for the repair of the equipment.”
→ A binary generator consists of two closed systems, beginning with the production and injection wells.
→ The production well is drilled into the deep, hot geothermal reservoir from where the hot steam or geothermal fluid is pumped to the surface.
→ The hot steam is passed through a heat exchanger and then injected back into the reservoir through the injection well.
→ When the hot geothermal fluid is sent through the heat exchanger, a secondary fluid is used to absorb the heat. This secondary fluid is similar to the refrigerant that is used in domestic refrigerators.
→ This heat transfer fluid is flashed to a vapour, which then drives the turbine that generates electricity.
→ The vapour is condensed back to a liquid in the condenser.
→ To complete the cycle, the vapour is then directed back into the heat exchanger to once again absorb heat in order to continue driving the turbine.
→ There are no emissions at all at the surface from this primary energy production system.
Such technological developments have made geothermal energy far more competitive in terms of the cost per kilowatt-hour in comparison with fossil fuels, as well as making it significantly cheaper than other sources of renewable energy, such as solar and wind power. Significantly, geothermal energy is the only base load renewable energy system available at present.
“Up until this point, it has always been the big coal plants, natural gas plants or nuclear plants that [have been] able to provide the base load, and then other specialist plants, such as solar and the wind systems, are used for the peaking load,” says Cutright.
Geothermal plants, on the other hand, can run a constant output for long periods of time without any variation. At the same time, they can vary their output very rapidly, which is achieved simply by increasing or decreasing the flow from the wells. By contrast, going from a cold start to generating electricity with a coal plant can take as long as four to eight hours, while it could take weeks to bring a nuclear plant online.
“Perhaps the key advantage for geothermal is both the base load capability and its ability to follow the load as the load increases or decreases on the general grid system”, says Cutright. “You can ramp up a geothermal plant in five, 10, 15 minutes – so you can go from 30 percent output to 90, 100 percent output in minutes. It can follow an increasing load demand very, very quickly and can meet variable loads, while at the same time act as a base level plant… You can’t do that with a big coal plant or a nuclear plant.”
While substantial developments are being made towards the 2021 goal for clean energy, there are other areas of the country’s carbon footprint that are not progressing at the same rate. In particular, a considerable amount of pollution is produced by automobiles within Costa Rica, largely as a result of the country’s major tourism industry, which in 2013 accounted for 12.1 percent of the GDP, according to the World Travel and Tourism Council.
Costa Rica is making efforts to incorporate hybrid and electric transportation into its environmental strategy. It began over a decade ago with the introduction of the Toyota Prius, which has been followed by the Indian Reva and the Mitsubishi i-MiEV. The government is also offering support for the movement through incentives, compensating for the higher prices of electric and hybrid vehicles.
With a population of around five million, there are some critics who argue Costa Rica’s small size and limited manufacturing sector enables its clean energy capabilities, and so more populated and industrial nations would not be able to employ such a high rate of renewable energy generation. This case is supported by the country’s per capita electricity consumption, which is considerably lower than that of more developed states.
“Costa Rica is not exceptionally blessed with natural resources; there are many other nations that have equivalent natural resources, but what Costa Rica has is the national will to make a difference”, says Cutright. Political determination, a highly educated populace and a cultural drive to protect the environment are what makes Costa Rica unique in terms of its sustainability practices. “It’s this national recognition of the importance of their natural ecosystems that I think makes them stand out among other governments in the area”.
Of course, Costa Rica’s small population and service-driven economic model have helped its advancements in renewable energy, but it has other aspects that arguably could have held back its achievements in the field but have not. The country’s commendable levels of conservation and sustainability come down to an exceptional degree of environmental awareness, which is deeply ingrained in the national consciousness. With the 75-day triumph to boot and its work towards the 2021 goal, this small country is a role model for the rest of the world and a fine example to all advocates of clean energy.