David MacKay is a Professor in the Department of Physics at Cambridge University and recently published a book ‘Sustainable Energy – without the hot air’.

Secretary of State Ed Miliband said: “David MacKay is known for making science accessible and helping to explain clearly the urgency and the challenges of moving to a low carbon economy. I want him to bring all of these qualities to the job of advising DECC on how we can meet Britain’s carbon targets and energy security needs.”

Mackay said “Climate change and secure energy are two of the most urgent issues facing the UK and the global community. The solutions must be rooted firmly in the science and I look forward to advising the Government on how it can help deliver these important goals.”

Mackay has caused a mixed reaction amongst renewable energy supporters mainly due to different interpretations of his book. It is easy at first glance to believe he is saying that renewables are just not up to the job of meeting our energy needs. However a different angle as put by Paul on Zerocarbonista is that what he is really saying is that renewables could never meet our present day demands “without considerable inconvenience”.

This is a very topical issue in the renewable energy industry as people expect wind energy projects to cause absolutely no effects on people (e.g they should not be visible from houses, national parks or in fact anywhere). As a population we need to accept that change needs to happen and some of that change may affect us at an individual level.

The report outlines the current technological status and growth of our favourite energy technologies, together with the key challenges and barriers for further development.

Wind energy is top of the list – described as a mature option in sustainable energy with great potential and a rapid development over the past 25 years. It has seen a healthy annual average growth and now makes a meaningful contribution towards global energy requirements. Seeing even larger increases in annual growth are the solar and geothermal technologies.

The Riso Report produced by the Danish National Laboratory for Sustainable Energy outlines development perspectives for energy supply technologies, new energy systems, end-use energy efficiency improvements and new policy measures. It also includes estimates of the CO2 reduction potential for different technologies.

A comparison of the reported annual average growth rates of wind energy compared with other technologies is listed below together with total share of global energy mix and potential share of global energy mix comparisons:

Wind
Annual average growth: 17.1 percent
Total share of global energy mix 2007: 3.3 percent of electricity
Potential total share of global energy mix 2030: 29.1 percent of electricity

Solar cells
Annual average growth: 40 percent
Total share of global energy mix 2007: 0.1 percent of total supply
Potential total share of global energy mix 2030: 1-2 percent of electricity

Solar thermal
Annual average growth: 17-20 percent

Biomass-based fuels for transport
Annual average growth: 6.3 percent
Total share of global energy mix 2007: one percent of transport fuel
Potential total share of global energy mix 2030: 10 percent of transport fuel

Biomass – combustion, gasification and pyrolysis
Potential total share of global energy mix 2030: 25 percent

Fossil fuels – combustion and gasification
Annual average growth: coal: 1.8 percent; gas: 2.3 percent; oil: 1.3 percent
Total share of global energy mix 2007: coal: 25 percent; gas: 25 percent of electricity; oil: 37 percent
Potential total share of global energy mix 2030: coal: 25 percent; gas: 31 percent of electricity

Nuclear energy (fission)
Annual average growth: 0.7 percent
Total share of global energy mix 2007: 16 percent of electricity
Potential total share of global energy mix 2030: 10 percent of electricity

Fusion energy
Total share of global energy mix 2007: zero

Geothermal energy
Annual average growth: 20 percent
Total share of global energy mix 2007: 0.4 percent of total supply
Potential total share of global energy mix 2030: two percent of total energy mix

Hydro, ocean, wave and tidal
Annual average growth: two percent
Total share of global energy mix 2007: hydro: 16 percent of electricity; wave, current and tidal: zero
Potential total share of global energy mix 2030: hydro: 16 percent of electricity; wave: 10 percent of electricity

The research carried out by AEA found that although green house gas emissions from energy generated using biomass crops is generally less than from fossil fuels, this is not always the case. Burning straw for example can produce over 35% more than a combined cycle gas turbine power station.

The report says that transporting fuels over long distances can reduce emissions savings made by the same biomass fuel by between 15 and 50%. Changing land use from fallow land to biomass crop growing land can also have a negative effect.

The report urges best practice for biomass crop producers and users. Power stations should be designed to utilise the heat from the outset and more Renewable Obligation Certificates (ROCs) should be offered for combined heat and power and heat only biomass plants.

Mandatory reporting on greenhouse gas emissions by generators should be required say the Environment Agency and a review of energy conversion efficiency in biomass heat and power generation should be carried out. The recommendation to carry out further research to understand which technologies will deliver the greatest emissions savings, suggest that the use of biomass will remain a hot topic over the next few years. Real examples of responsible fuel sourcing and emission saving power plants will be needed to persuade the world that it can contribute to a healthy and sustainable energy mix.