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World Energy Crisis – Your Questions & Answers
Here are the questions that you asked about the world energy crisis... and Prof Jim Skea's answers.
Q1 | Q2 | Q3 | Q4 | Q5 | Q6
Question 1
How effective compared to oil and gas are the major alternative technologies available today – namely wind, biofuels, solar, tidal and wave?
Stan P, Portsmouth
Professor Skea: A key point about energy policy is that no single technology provides the answer. We're going to need a mix of production technologies. The technologies you mention all have a potential role to play. Most of them, other than biofuels and solar hot water heating, are associated with electricity generation. They certainly won't displace oil for transport though they could push gas out of the equation to some extent.
Wind is the most mature of the electricity generating technologies you mention. Onshore wind in a good location is approaching fossil fuel generation in terms of cost. And the so-called intermittency problem (what happens when the wind doesn't blow) has been exaggerated.
Question 1
How effective compared to oil and gas are the major alternative technologies available today – namely wind, biofuels, solar, tidal and wave?
Stan P, Portsmouth
Professor Skea: A key point about energy policy is that no single technology provides the answer. We're going to need a mix of production technologies. The technologies you mention all have a potential role to play. Most of them, other than biofuels and solar hot water heating, are associated with electricity generation. They certainly won't displace oil for transport though they could push gas out of the equation to some extent.
Wind is the most mature of the electricity generating technologies you mention. Onshore wind in a good location is approaching fossil fuel generation in terms of cost. And the so-called intermittency problem (what happens when the wind doesn't blow) has been exaggerated.
Offshore wind has big potential but the costs are higher and more development is needed to get these costs down. Wave and tidal technologies are also less mature and need much more research and development before they can be used extensively.
Electricity from solar photovoltaics (PV) is expensive, but it can make sense already where there is no electricity grid. There is the possibility of big break-throughs in PV through research into materials which would allow us to do away with silicon-based cells and achieve higher conversion efficiencies.
Bio-fuels are intriguing because they offer the prospect of breaking the link between oil and transport, possibly the most vulnerable part of the energy equation. Existing bio-fuels from food crops such as sugar, maize or oil seed rape, don't help as much as we would like in reducing carbon dioxide emissions over their life cycle. To address that we need to move to "woody" biomass – trees such as poplar or willow – or grasses such as miscanthus, often (but wrongly) called elephant grass. A huge amount of research could be carried out here on crop improvement through breeding, and perhaps more controversially, genetic modification. Research is also needed on conversion of bio-crops, for example in dedicated 'bio-refineries' analogous to petroleum refineries.
But bio-energy isn't about changing the technology as much as changing the system. We need to understand better the impact of bio-crops on landscapes, ecosystems and biodiversity. We also need to understand better the trade-offs between land use for food production and land use for bio-energy. So, the technologies you mention may be available today but, apart from wind, further development is needed and the real potential will be realised tomorrow.
Electricity from solar photovoltaics (PV) is expensive, but it can make sense already where there is no electricity grid. There is the possibility of big break-throughs in PV through research into materials which would allow us to do away with silicon-based cells and achieve higher conversion efficiencies.
Bio-fuels are intriguing because they offer the prospect of breaking the link between oil and transport, possibly the most vulnerable part of the energy equation. Existing bio-fuels from food crops such as sugar, maize or oil seed rape, don't help as much as we would like in reducing carbon dioxide emissions over their life cycle. To address that we need to move to "woody" biomass – trees such as poplar or willow – or grasses such as miscanthus, often (but wrongly) called elephant grass. A huge amount of research could be carried out here on crop improvement through breeding, and perhaps more controversially, genetic modification. Research is also needed on conversion of bio-crops, for example in dedicated 'bio-refineries' analogous to petroleum refineries.
But bio-energy isn't about changing the technology as much as changing the system. We need to understand better the impact of bio-crops on landscapes, ecosystems and biodiversity. We also need to understand better the trade-offs between land use for food production and land use for bio-energy. So, the technologies you mention may be available today but, apart from wind, further development is needed and the real potential will be realised tomorrow.
