Sunday, April 6, 2014

Energy: Choices we make

“All serious mistakes are made on the day One. Worse yet, you may have to live with them for decades”. This was said about project development, but can also be applied to political decisions and national strategy.

The case in point: Australian National Broadband Network.

Canada (as the rest of the world) is currently at a crossroad in respect to its long-term national energy strategy. What choice will we make? Here are some of the possible options:

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Coal

Coal is one of the traditional and still the "cheapest" sources of energy. It is however recognized even by its proponents that its impact on the environment, mostly  CO2 emissions, is not something which can be ignored. The so called "clean coal" is only a temporary solution - as its business case based on the purchasing of the recycled CO2 by the oil industry (see Clean Coal - Is It for Real?)  - until other alternatives will make it unnecessary and obsolete.   

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Gas

It seems the world turned 180 degrees since just few years ago since the new reserves and new technologies of extracting oil and natural gas came to light. We seem to forget the concept of the "oil peak" popular a decade ago and tend to ignore now that even with comparatively lower direct CO2 emissions from natural gas there are many other negative factors associated with the oil and natural gas, particularly methane (which has 23 times more greenhouse potential than natural gas itself) and other harmful bi-products. What especially bothers me is that choosing this way will only prolong our addiction to fossil fuels and divert resources and capital from developing real clean alternatives - thus making inevitable migration away from fossil fuels in the future more painful      
Safety is an additional - and ever increasing concern. The oil and gas extracted from Northern Alberta or other places has to be delivered to the processing plants and eventually to their end-users. Pipelines are susceptible to leaks and to terrorism. Delivery by train carries an inherent danger which was tragically demonstrated by the derailment and explosion in Lac-Megantic. Also, the risk of spill from tankers, however small it can be, may as it already had in the recent past, have very serious consequences.      

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Hydro


Electricity produced by hydro plants is generally considered "clean". One of the best examples of it is British Columbia where 90% of electricity is produced by hydro plants. At the same time construction of new large hydroelectric dams, like the one is planned in the Peace River region of British Columbia (Site C dam C dam), is met with increasing and well justified resistance due to the large areas of agricultural and lands with valuable habitat would be lost.  An ambitious plan to build a large number of hydro dams in China which is in desperate need of energy while reducing air pollution causes the same concern.   

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Nuclear


It is impossible to discuss nuclear energy within few paragraphs without addressing both its high output, nuclear industry reliability track record, but also potential dangers of catastrophic failure and enormous complications related to storing of nuclear waste. I will limit the discussion by one comment only - assuming all hurdles of such endeavor as new nuclear project are overcome, it will take many years and billions of dollars of capital investment  to implement such a project.


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Wind 


Wind turbines are a source of clean energy and become increasingly popular and wide-spread, especially in Europe. The capacity factors and useful service life of industrial wind turbines (IWT) are important determinants of levelized wind energy costs. However, some recent studies have brought to light the capacity factors are less and useful service life is shorter than typically assumed. Based on analyses of actual production results, it appears the capacity factors of wind energy projects in many areas of the world are much less than previously estimated. As a result, the capital costs and environmental impacts of implementation would be much greater. It is typically assumed that the life span of the wind turbine is 25 years. But even 20 years may be too optimistic.

The analysis of almost 3000 onshore wind turbines in the UK - the biggest study of its kind - warns that they will continue to generate electricity effectively for just 12 to 15 years.
The “load factor” - the efficiency rating of a turbine based on the percentage of electricity it actually produces compared with its theoretical maximum - is reduced from 24 per cent in the first 12 months of operation to just 11 per cent after 15 years.
Icing in the Northern and mountainous regions is a factor significantly affecting the turbine's efficiency and is often underestimated. 
Because of the moving parts and exposure to the external environment, wearing of equipment require regular maintenance, and more so the longer it is in operation.

Transmitting energy from the wind turbines incurs energy losses, which is a serious addition to other losses when located in remote areas which typically is the case.
Finally, the impact on habitat. In the US alone wind turbines kill more than 14 million birds and 42 million bats a year!   
  
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Geothermal


Geothermal electrical plants is another source of clean energy because it does not require fossil fuels to be burned . A big advantage of the geothermal energy is its reliability and consistency comparing to wind or solar. It has its challenges however.
Open geothermal systems emit air pollutants. This include hydrogen sulfide, arsenic, and some toxic minerals. Mineral build-ups are frequently deposited in landfills. Closed loops avoid this problem.
The equipment and installation are both very expensive. Despite their long-term cost savings, geothermal plants have very high up-front costs. Installation can also be very destructive. It requires significant amount of drilling and digging around. Also, the under surface footprint of a geothermal plant is much larger than its above surface footprint.

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Solar

Sun gives energy for life on Earth and is one of the best sources of energy we could think of. It is clean, safe and because we know pattern of its movement across the sky, is also predictable. There are several ways of utilizing solar energy.

    Solar Photovoltaic


More familiar for most people than other solar technologies, photovoltaic (PV) technology originated first in space applications, found ts place in commercial and residential market and are even entering transport - from airplanes to ships (e.g. see Electric Aircraft  and  Solar Ship).
While their efficiency is still low to compete with any conventional or other alternative sources on a cost basis, solar PV modules have one extremely important advantage - they involve no moving parts, meaning practically no maintenance, and also zero noise.  
Despite recent dramatic improvements in efficiency and reduction in costs, solar PV systems  have a very long payback period, which holds their large scale implementation.

   Solar Concentrated Plant
 
These exotic looking installations with thousands of mirrors are popular in Europe, particularly in Spain, and are most efficient in regions with high solar irradiation like in in Africa, or California deserts. They require large secured unpopulated areas which limits where they can be deployed. Their efficiency can also be seriously reduced when the reflecting surface of the mirrors is damaged by sand storms and other factors.  

   Solar Updraft Tower 

This a concept which utilizes energy of the heated air rising in a very tall pipe with a fans inserted in it, connected to a generator - a sort of vertical wind turbine. Due to its relatively low efficiency and the lack of expertise these kind of systems did not receive wide acceptance in North America.




[to be continued]

1 comment:

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