Geothermal Power: An underrated alternative source of energy

30 03 2010


For today’s post I am very excited to introduce my friend Peter Buchanan as my first guest writer for ReachFWD.

Peter is currently studying Petroleum Engineering at the University of Alberta and he hopes to study geothermal electricity at grad school. He was explaining the concept to me and it sounded so interesting that I asked him to write a brief explanation for my readers on ReachFWD.

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When we think of alternative sources of energy, renewable resources that can reduce our dependency on fossil fuels to meet our energy needs, often the most vivid pictures that come to mind are wind and solar power. Evidently, this is because the sun and the wind are so ubiquitous in our daily lives. We can feel their energy so it is only natural to notice them. This is probably why geothermal power, another renewable source of energy has been largely overlooked until recently.

Geothermal power comes from energy generated by heat in the earth. The material that makes up our planet gets hotter and hotter as is gets closer and closer to the core of our planet. This energy can be seen on the surface in the form of hot springs, geysers and volcanoes. There is an essentially infinite amount of energy beneath our feet, waiting to be utilized.

(Diagram from www.geo-energy.org/basics.aspx)

Geothermal Energy is not new; the first Geothermal Power Station was build in 1911 in Larderello, Italy[1]. Since then, it has become a common source of energy in places like New Zealand, Iceland, The Phillipines and the Geysers in California. Typically it works like this: Two wells are drilled into a geothermal reservoir (rock hot enough to transfer sufficient energy to water). The geothermal reservoir may contain water or steam in network of pores and fractures that make up the rock or it might be dry. Hot water is extracted from the wells and its energy is used to drive a turbine which generates electrical power. The cooled water is then re-injected down the other well where it reheats and continues in the loop.

While there are various types of geothermal plants, the three most prominent types are: Flash steam, Dry steam and Binary Cycle.

Flash steam plants work when high pressure, high temperature water coming up the producer well are directed in to a large vessel. Because of the large pressure difference the water flashes into steam which is used to power the turbine.

Dry steam plants are used when the wells produce only steam. This can be the case in very high temperature reservoirs. The steam from the reservoir directly turns the turbine and is then condensed into water and re-injected into the ground.

Binary Cycle plants use a working fluid (commonly iso-pentane) with a lower boiling temperature than water to turn the turbine[2]. Hot water from the reservoir heats the fluid in a heat exchanger. The fluid then boils to turn the turbine, while the water is re-injected in a closed loop. Binary Cycle plants allow for lower temperature reservoirs to be used.

(Diagram from: http://www.nevadageothermal.com/s/HowGeoWorks.asp)

If geothermal power is so clean, efficient and abundant, why isn’t it being used for all of our electricity needs across the planet, you ask? Until recently, geothermal power was not viable from and economic or technological point of view in most areas of the world. In places like Iceland, New Zealand and the Philippines where hot reservoir rock can be found close to the surface it was used but in many areas of the world the resource would be too deep to drill for economically if even possible.

(Diagram from: http://www.cangea.ca/what-is-geothermal/)

Fortunately, with today’s advancements in technology such as binary cycle plants and enhanced geothermal systems (EGS; where rock is artificially fractures to allow for more permeability in the rocks and more flow/heat transfer) many new geothermal resources may be unlocked in the near future. Geothermal power is not likely to ever completely replace fossil fuels, however combined with other renewable sources of energy it has the potential to contribute to a much larger percentage of the world’s energy consumption.

Pros of Geothermal Power:

  • Clean and renewable with little or no emissions.
  • Reliable. It doesn’t depend on the weather to produce electricity, so it is always on.
  • Many of the engineering concepts are very similar to Oil & Gas, so we have a head start on the learning curve.
  • Can already compete economically in some regions and the list of regions is growing.

Cons of Geothermal Power:

  • Requires a large initial capital investment (like all power plants) which can take time to recover the costs.
  • Not economical in many regions.
  • Reservoirs can be depleted of heat locally, but will regenerate the heat over time.
  • Not enough awareness!

References:

  1. Larderello Worlds First Geothermal Power Station, Renewable Energy UK,  http://www.reuk.co.uk/Larderello-Worlds-First-Geothermal-Power-Station.htm
  2. How Geothermal Works, Nevada Geothermal Power, http://www.nevadageothermal.com/s/HowGeoWorks.asp
  3. What is Geothermal, Canadian Geothermal Energy Association, http://www.cangea.ca/what-is-geothermal/
  4. Basics, Geothermal Energy Association, http://www.geo-energy.org/basics.aspx
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Global Pulse 2010 – A 3 day online forum for international development

29 03 2010

Today marks the first day of Global Pulse 2010. From Monday March 29th  to Wednesday March 31st 2010, the U.S. Agency for International Development is partnering with the U.S. government’s departments of state, education, commerce, health and human services to bring you an online collaboration event unlike any other! The U.S. Government wants to engage, and partner, with the international community in a meaningful way. Everyone can join the conversation which will hopefully help to shape the future.

As self-described on their website:

Global Pulse 2010 is a 3-day, online collaboration event, that will bring together individual socially-engaged participants and organizations from around the world.

As the name implies, the event will take the pulse of thousands of participants on key issues facing communities around the world. Global Pulse 2010 will connect participants who are champions for the same social issues to build new, or strengthen existing relationships, and inform U.S. foreign assistance and diplomatic strategies on major themes and ideas that emerge across the span of the event.”

*This event is free, and open to everyone who feels that they have something to contribute to the event. Other bloggers, please note – they have specific rules in place for blogging about the event, which can be read in the rules when you sign up.

Sarah Topps (See you on the forums!)





The good ol’ hockey game…

20 03 2010

Written: February 24th 2010

Today I had a revelation: sitting in my chair, reading a fictional novel by the bright sunlight streaming through my window, I realized that electricity had only been in use by humans for about a century. As I was contemplating this, and the sheer technological advancement of the last century, I heard a cheer go up from the 300 people around me. Surprised, I looked up, and saw that the first goal had been scored against Russia in the Olympics. ‘Oh right,’ I think to myself, ‘it’s 4:40pm, the hockey is on.’ Pressing the buttons on my armrest, I change the T.V. in front of me to the big game, and glance out my window through the clouds to admire the glacier-topped mountains thirty-five thousand feet below me. My ears pop as the captain announces the weather in the city where I will be landing shortly, and I try to imagine how mind-blowing this situation might be for someone who was born in the 1880s rather than 1980s.

In this day and age, when we talk about ‘development’, we never stop to consider that we ourselves are developing at a remarkable rate of change, and that any nation who didn’t begin their ascent with the affluence and influence that countries such as Great Britain…*GOAL!* …or France, or even Russia, I suppose (although we’re still beating them in hockey) started with, who is still keeping up with us in terms of economic prosperity and social development indicators must be a great nation indeed. It is mind-blowing to consider that whole countries are simply skipping points of technological development which we underwent, such as landline telephones, and jumping straight into portable internet phones – The UN is projecting over 5 billion cell phone accounts, over 1 billion of which are broadband accounts also, by the end of 2010. This is mind-boggling, considering the current population of the planet.

There is something remarkable and empowering about being on a plane full of cheering Canadians while the national men’s hockey team battles for a medal forty-thousand feet below and 400 kms away.

– Sarah Topps





To master or not to master?

18 03 2010

As an honours student at a top university, I have been frequently asked what my post-grad plans are in the months leading up to my graduation. Many of my peers have applied to grad school, and many will succeed, given the competitive push amongst those of us who have lasted through our undergraduate degrees. I thought I would investigate this line of thinking and see how common my choices were…

My top choices currently stand as follows:

1. Masters of Public Health at Simon Fraser University

2.  Travelling to Cameroon to work with Aquacare, a locally-founded organization which is promoting SODIS (solar water disinfection) – the topic of my current thesis

3. Travelling to Angola to work with Karen Henriksen and the Centro Evangelico de Medicina de Lubango (although I would need to learn more Portuguese first)

4. Masters of Public Health at Queen’s University (although more of an Epidemiology focus than SFU)

5. Working as the Morocco consultant for the Rickshaw Travel company located in Brighton, England

6. Working temporarily for Norwegian Cruise Lines (NCL) – a job I’ve already been interviewed for, that would help me work off my student debt, let me travel and improve my language skills

There are others, but those are the top ones which appeal to me at the moment. Several internships also appeal, although I plan to find out if my applications to grad school are successful before applying.

Being at university, and especially as a B.A. student, I often feel as if everyone and their dog has a university degree these days – which can be seen in both a positive and a negative light. After applying to grad school, I thought about the number of my friends from high school who didn’t go to university, and wondered what the national statistics had to say about the matter.

The answer is surprising – only 19.4% of Canadians (2007) have completed a university degree. This includes all bachelors degrees, masters and PhD’s in the country. If you also include CEGEPS, colleges and technical degrees, diplomas and certificates, the number rises to 46%, which is apparently the highest proportion in the world!

Wow. I feel much smarter now – thanks Google! I have been so immersed in the academic environment for the past 5 years that I haven’t stopped to realize both how lucky and how talented we students are as a group of people in this country, and globally. Having realized this, and knowing that the rate for a master’s program must be that much lower, I’m still keeping my fingers crossed for being accepted. I just hope that I have eased someone else’s mind in the process of writing this!

– Sarah Topps








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