Why Should I Care?

We hear a great deal of talk today about ‘Renewable Energy’, sometimes in conjunction with climate change and environmental implications and also in the context of the fact that our primary sources of energy today are not endless. It is expected that global energy demand will double between 2005 and 2030. At the same time the various fossil fuels, such as oil, natural gas and coal, will eventually be depleted if they continue to serve as the primary energy sources for this planet. Estimates on depletion vary significantly and are usually biased by the source of the estimates, so we will not delve deep into that concept today (if anyone thinks they know a credible source of estimates that takes into account future demand, feel free to comment).

For today’s discussion, the following premise is going to serve as a basis of this conversation: In 2005 over 85% of the world’s energy production came from these fossil fuel sources that are not unlimited and each contributes CO2 (a greenhouse gas) to the atmosphere. So whether you want to have energy for future generations or are concerned about the climate implications of fossil fuels or even both, this topic should be of interest to you. If you fall into one of those 3 camps read on, if not, well I am sure you could spend your time better somewhere else.

How we make a transition from these traditional energy supplies to new sources should take at a minimum two things into consideration – is the source renewable or ‘essentially’ inexhaustible, and is it economically, technologically and environmentally viable. What fits the bill as ‘renewable’, certainly that depends on your definition, but from some difference sources (EIA, UK-REC, NREL, Nuclear Scientist) we come up with the following list – Biomass, Geothermal, Hydro, Hydrogen, Nuclear, Solar, Tide/Wave, Wind. Let’s take a look at some basic pros and cons of

• Biomass: pros – can be made from lots of crops / plant types, can even reduce other waste types, can have lower emissions results (plant versions about carbon neutral); cons – alter planting schemes and natural vegetation patterns, impact food prices, not particularly efficient, in some cases still has other pollutant emissions
• Geothrermal: pros – generally low emissions in energy transfer, high efficiency for direct heat generation; cons – not widely available, generally small quantities available, not efficient for energy prodcution
• Hydro: pros – input water output water, newer versions exist that have less environmental impact,  well developed technology; cons – traditional systems have major environmental implications, high initial costs, newer technologies have fewer placement options
• Hydrogen: pros – most abundant element in universe, translatable into different forms (liquid, gas, fuel cells), storable; cons – not naturally available on earth in gas form, creates another greenhouse gas as an emission concern, currently not an efficient technology
• Nuclear: pros – quantities sufficient to last as long as sun, established technology with proven results; cons – emissions highly volatile and dangerous, technology convertible into dangerous weapons
• Solar: pros – no emissions, available to certain levels around the globe, virtually unlimited source; cons – only available half the day, production also influenced by weather, technology still not efficient and costly startup
• Tide/Wave: pros – water in water out, steadily predictable source; cons – alters navigation and aquatic life, location limitations, relatively young technology, ocean tough on equipment
• Wind: pros – input wind output wind, new turbines less threat to wildlife, developed technology; cons- bird migration/death issues, visually displeasing, can have climate impacts, limited placement options

Ok, we have some options, each with pros and cons. Of course some a bit better on the pros and lighter on the cons that we have considered up to this point, but that said, all these technologies are not created equal. It is also important to keep in mind that we have different energy need types, for simplicity sake let’s just call them stationary (eg. building electricity, heat, cooling, etc.) and mobile (eg. powering cars, boats, planes, etc.). It may also be that what works in one part of the world may not work in the others. So which are really viable?

In our consideration of ‘viable’, we return to our three considerations of economics, state of technology and environmental impact. The United Nations Development Programme has a good summary report on these considerations from a report generated in 2004. Still, ‘viable’ – such a tricky word, meaning very different things to everyone. So here is my take on the viability of each of these sources:

• Biomass – while it is essentially carbon neutral it can in many cases create other pollutants, however it might be the best short term solution for our ‘mobile’ energy needs. Its impact on global food costs at current production price points however is a real concern, again likely a short term solution until the technology uses all plant parts, making a harvest of a food crop beneficial for both agricultural and energy.
• Geothermal – probably better for heat production than anything in use already, but limited to places like the ‘ring of fire’ or hotspots like Iceland. It should be leveraged as part of the mix, but geographic limitations will likely make this a small chunk of the renewable pie.
• Hydro – already in use and the most common of renewable energy sources is use to day, however I think its impact on the environment is too high. In stream designs show some potential, but given the limitation on where this type of technology would work, it seems like hydro power is a short term solution to a long term problem.
• Hydrogen – with current technologies, not particularly efficient, but has great potential to be a long term ‘mobile’ energy source. The emissions issue is real and the thought of replacing one greenhouse gas with another needs to be considered, maybe capturing the vapor and utilizing it in liquid form (a.k.a water) will address that issue.
• Nuclear – yes there are some real concerns with this technology, but might it not be a viable choice for the next 20-50 years until these other technologies become more developed?
• Solar – is just too costly today, large up front costs and still not an efficient technology. There is no doubt however that IF efficiencies can be improved that this is a source of choice, but its availability is not equally global so no one should consider this as the sole future of renewables.
• Tide/Wave – possibly one of the most predictable sources of energy, but currently challenged by technology costs and will always have limited placement considerations. Long term this is potentially one of the strongest solutions, but until cost come down and some of the environmental issues are addressed, this one will be of limited use.
• Wind – proven technology with costs in line with fossil fuels, however limitation driven by viable locations and potential changes in weather patterns limit its use to certain geographic areas. Off shore wind farms probably show the most promise, but it is likely that this technology will remain limited to certain geographic regions.

So, where does this leave us? It seems that each energy type mentioned fits the ‘renewable’ tag and has some level of viability. Some may be best suited for the short term (nuclear, hydro, biomass, wind), some more so for mobile energy needs (biomass, hydrogen), and some more regionally oriented (geothermal, tide/wave, solar, wind). However, in the end it will be a mix of technologies that serve the energy needs of this planet going forward, and it is important to realize that there is no magic single source in our current understanding of science and technology. At the same time it seems completely feasible that a combination of these technologies can replace fossil fuels in energy production, but don’t expect it overnight and don’t expect it with current levels of technology development.

This post has certainly taken a wide brush look at this topic, and in future posts we will probably dig into some of these individual technologies and their feasible potential and realistic limitations. For now, the topic is turned over to you the readers to share your thoughts and ideas.

1. Which sources do you think should get the most development attention?
2. Which do you think are most viable?
3. What is an acceptable level of environmental risk?
4. And why in the world would a US stimulus package focus on building more roads instead of investing in furthering these technologies?  Sorry, couldn’t resist that last one