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The making of a globally sustainable energy system

StevePye14 November 2016

sustainable world (c) istockphoto

Blog by Steve Pye, Paul Ekins, Ian Hamilton, November 2016

As delegates at COP22 in Marrakech convene to discuss how to implement the Paris Agreement, there is a continuing focus on how to move to a sustainable global energy system. The challenge is that fossil fuels have long been the mainstay of the energy system, and an essential driver of growth. Rapidly reducing our reliance on their use is no small task, but one that is essential if we are to succeed in achieving the climate ambition set out in the December 2015 Paris Agreement.  The challenge is brought sharply into focus when we consider that the global energy system accounts for 65% of anthropogenic GHG emissions[1], but will need to be a net zero-emitter at some point between 2050 and 2100.

The challenge

The barriers to this transition are immense. (more…)

Among China’s top three energy sources, two are now renewable

BoranLi12 December 2014

While browsing online for information about electricity generation from renewable sources, I found a rather surprising “olds” reported by CleanTechnica back in January 2013, that China’s electricity produced from wind has already surpass the amount from nuclear, hence became the third largest source of electricity. This implies a seemingly impressive achievement: among top three energy sources in China, two of them are renewable, hydro and wind power. This is really remarkable, even compared with most developed economies in the world. Based on data provided by IEA, advanced economies including the US, the UK and Germany have their electricity mainly from coal, gas and nuclear. None of these sources is renewable!

boran liShould we applaud for this achievement of China, one of the biggest polluters in the world? Ehhh, probably we need to look deeper into this firstly.

One reason behind why wind could make its way into the top three is that the top two sources produce more than 93% electricity in China; more specifically, around 76% from coal and 17% from hydro (around 5% for wind in 2013). With this two big players in electricity generation, it is not that hard for other new growing technologies to join the team of top three, while no significant impact upon carbon emission could be realised during this process. Even though, the 17% figure for hydro itself also looks very impressive. But recently, there are many debate in China about if it is worthy to decarbonise by building dams, considering their significant by-product of damaging local ecosystems. The biggest dam in the world, Three Gorges Dam, was once a national treasure of the Chinese public and an important showcase of the powerful Chinese government, but if you search on the internet now, all you get are its damages to local weather, endangered species and reservoir area geological structure. Due to lack of rigorous planning and impact assessment before constructions of many government hydro-power projects, and countless resulted side effects, it is a growing consensus in China that all the dames will all be pulled down, sooner or later.

Similar problems occurred to wind energy development as well. For many local governments, one of the main objectives of developing wind energy is vanity of local officers. This leads to the issue that local government lacks incentives and therefore expertise to conduct detailed planning before building up wind power plants. In many cases, poor integration planning and inadequately developed electricity storage technologies raised the issue of electricity waste. In 2013 the amount of wasted electricity was estimated to be equivalent to the whole year usage of Beijing, this means only 2.5% of actual consumed electricity in China came from wind last year. Compared with the 5% production figure, half of them was thrown back into the air. Moreover, in some extreme cases, government officers only realised the wind power plant was not connected to the grid after the construction was finished.

We should not deny the great achievement that wind produced electricity in China soared 1580% from 5710GWh in 2007 to 95978GWh in 2012, which cannot be done without a strong centralised government. In less developed market economies like China, private businesses may take longer to respond to changes of market signals and advances of technologies, it is therefore government’s responsibility to plan and build the future. But with a strong Soviet style planning tradition, Chinese government still need time to learn how to give the freedom back to the market. Nowadays, even with generous subsidies provided by the central government, many green-tech businesses are complaining that they are physically crowded out by large scale wind and solar power plants invested by local governments. This conflict of crowding-out is set to be more intense in China than in well-developed democratic countries, considering China’s capitalist economic based and the single party bureaucratic (deliberately avoid using a strong word) upper structure. Given all the negative impacts from state initiated projects, it might be high time for government to learn when and where to take its muddy hands off, and let the market go.

Everything we do contributes to climate change

CarolynBehar7 March 2014

Blog by Carrie Behar, UCL-Energy PhD student
Get invovled in the conversation: Follow Carrie on Twitter – @LoLoStudent

Being asked to prepare a blog post for this year’s climate week got me thinking about how my work relates to climate change. To me, climate change is a huge and scary thing. It feels totally beyond my control, and if I do spend too much time thinking about the magnitude of the problem, I feel like giving up altogether and running away to aDream 3 desert island. The problem is, if we all did that, it would be only a matter of time before all the desert islands got full, that is if they weren’t first subsumed by rising sea levels.

Another problem with desert islands is their lack of high speed broadband, lively high streets with shops and bars, and comfortable spaces where I can sit and think and read and write, occasionally engaging in stimulating conversations with my colleagues, or grabbing a bite to eat in a local café. Furthermore, much as I like the idea of spending my evenings lying in a hammock under the stars, I also thoroughly enjoy my own personal routine of waking up in a warm and comfy bed on a Saturday morning and then wasting an hour or so playing on Twitter whilst building up the motivation to face the gym!

So here I am, and here are lots of us, living our lives very much within the constraints of the culture within which we were born and raised. We live in heated (or cooled) houses and flats, eat food imported from all over the world, travel longer distances that we feel comfortable with to get to work or school, and spend much of our time indoors, usually connected to some kind of electronic device. And allReality 3 of these activities, consume energy – lots of energy. This energy that we rely on to live our ordinary lives is generated from a combination of burning of fossil fuels and utilising renewable resources such as wind and solar. And it is the burning of fossil fuels that is accelerating the changes we are seeing in our climate, as explained here.

 

What can energy demand research do to help?

Ultimately, the reason I am here, doing my PhD and writing this blog is because, recognising the contribution of energy consumption in buildings to changes in the world’s climate, the UK Research Councils felt it was worth providing funding for PhD research in both energy supply and use. But what am I actually doing and what do I hope to achieve? And can I really make a difference with my tiny contribution to the vast pyramid of knowledge?

At first glance, looking at how people are adapting to living in new low-energy homes with ‘whole house’ ventilation systems is a long way away from working on ‘solving’ climate change (more about my work here). However, if we understand that energy used in our 27 million homes accounts for nearly a third of total UK energy use, it’s at least clear that there is a strong need to reduce the energy consumption of both new and existing dwellings.

As around 60% of domestic energy use can be attributed to space heating, an effective way of achieving this reduction is to seal up gaps and cracks around windows, doors, floors and roofs to make our homes more airtight and less draughty, thereby keeping the heat in. However, we cannot completely seal up homes, because the activities we carry out inside them generate a range of pollutants which need to be removed. Ventilation is the controlled provision of clean air and the removal of stale air, which typically contains CO2 exhaled by people, water vapour from showering and washing, and smells generated when cooking. These byproducts of everPyramid 3yday domestic activities must be taken out to keep us healthy and prevent nasty things like mould developing.

Why technologies alone won’t fix the problem

Several technical solutions have been proposed to deal with the problem of ensuring sufficient ventilation without wasting any heat energy. These are explained in detail in this Energy Saving Trust publication. The idea is that, during winter, air is only permitted to enter and leave through designated and controlled openings, such as trickle vents and ceiling extracts. The house stays toasty and warm, while harmful  pollutants are removed and replaced by fresh air from outside. Problem solved, right?

Unfortunately not. Although these systems have potential, the deployment of technology is not in itself a guarantee of success. Monitoring of energy consumption at completed homes which incorporate these systems repeatedly highlights the large gap between predicted and actual energy consumption. There are a number of factors that contribute to this performance gap and the way that people use and interact with their homes is but one of them. That’s not to say that people are necessarily doing something wrong; rather, there are a wide range of normal activities that we carry out which can impact on energy use. For example, do we regularly cook for family and friends or eat out most nights? Do we prefer baths or showers? And how much time do we spend at home and at what temperatures do we feel most comfortable?actual bath 3

When recommending, specifying or installing a specific ventilation system, there is an inherent assumption that the people living in the house will act in a certain way to get the best use from their technology. The ‘model’ resident would leave the windows closed at all times when the heating is on, and rely on the ventilation to do its job. They would press the booster button each time they cook or shower, and only dry their clothes on the designated drying rack in the bathroom. Furthermore, they would make sure the extract vents were kept free of dust and grease and ensure that filters are changed regularly so that system performance does not deteriorate.

We won’t improve anything without understanding people

Unfortunately this assumption fails to acknowledge the day to day realities of life. Very few of us go about our existence worrying about the energy consequences of our every activity. If we did, we would get very little done and end up a bit mad (and start thinking about desert islands and the like…).

saucepan 3Although you cannot, rightly, force people to behave in a certain way, I would like it to become easier for people to do the most efficient thing, and in the case of domestic ventilation I think we have a long way to go before this is the case. Over the course of my studies I have met people who are largely unaware of the presence of controlled ventilation in their home, let alone knowing what to do with it, as well as  a family with a broken booster button who had no option but to open the window to let out cooking fumes.

Completely unsurprisingly, I am yet to meet someone who is able to explain to me correctly what MVHR, MEV or PSV are and how they work (and if you didn’t get round to reading the Energy Saving Trust publication I mentioned earlier then you probably don’t either!). The residents I have spoken to have never been told that there are filters that need changing, nor that they could save energy and money by keeping the windows closed when the heating’s on. The reality is that we open the windows and forget to close them, dry clothes on radiators, put off housework until it is absolutely necessary and we find a way round things like broken switches that doesn’t involve us calling a handyman.technology 3

And this is why, I believe, the problem of climate change is so hard to resolve. Society seems to be driven by a desire to invent technical solutions  to fix problems. But when we break down the issue into smaller and smaller chunks, for example individual houses and their ventilation systems, we are always left with people and organisations interacting with material things  in unexpected ways and not just the objects themselves.  And it may just be that rather than relentlessly, modelling, simulating and optimising how technologies work, the solutions to global problems could lie in understanding how the minutiae of day-to-day life shape our energy use.

Carrie Behar

 

 

Climate Change and Water: Stores have a response in store

SimonDamkjaer5 March 2014

Blog by Simon Damkjaer, UCL ISR PhD student

Substantial increases in the combustion of fossil fuels over the 20th Century have led to a shifting climate, whose impacts on global water resources are best experienced through changes in the global hydrological cycle.  As part of a series of posts related to the 2013 UCL Energy and UCL ISR Climate Week, this blog post provides an overview of the most direct impacts of climate change on water resources and highlights my Doctoral Research on the importance of hydrological stores under a changing climate.

water_cycle

 

 

 

 

 

 

 

 

 

 

Ice sheets and glacier retreats
Climate change has been popularly coined “Global Warming”, and as the name itself suggests, means rising temperatures.  The first way, in which rising temperatures impact global water resources is through the transfer of freshwater from a state of solid snow and ice into water as a fluid state.  The ice-sheets of Greenland and Antarctica have been melting at alarming rates over the past decades [1], which has led to an increase in the mean rate of sea-level rise of 3.3 mm/year relative to a 20th Century average of 1.7 mm/year [2].  The effects of rising sea levels, simply put, will exacerbate the risk of storm surges at coastal areas.

Furthermore, snowfall over the polar ice-sheets is predicted to be reduced.  This, in combination with melting ice-sheets, will decrease the ice-sheets’ albedo effect – that is the amount of surface that deflects incoming solar irradiation.  A reduction in albedo effect risks triggering so-called feedback mechanisms, a system of circular loops, in which the warming of the global surface is enhanced, as less incoming heat is reflected due to a reduction in albedo which is caused by ice-sheet retreat due to rising temperatures and so forth.

Although alpine glaciers are currently melting at rates three times lower than that of ice-sheets, their impacts are still felt through effects on river flow, whose influence range from moderate in mid-latitude basins, to major influence in very dry basins.  The main issue related to an increase in glacier melt rate is that it causes a mismatch and unpredictability in the timing of dry period river flows, which has implications for access to water for agricultural purposes.

Precipitation, Evaporation and Transpiration alterations
The second way in which the global water cycle is affected by a shifting climate is experienced by the ability of hotter air to hold more water, which in return affects precipitation and evaporation rates.  The effects of increasing precipitation rates are felt at two extremes.  At the one end, rainfall events will be more extreme, short-term and variable, which will lead to increased run-off and thus higher flood risks.  At the other end, the intervals between these short-lived and heavy rainfall events, will get longer, which increases drought risks.
As temperatures rise, more water evaporates back into the air, which means less water availability for crops – “less crop per drop”.  Additionally, from a biological point of view, higher CO2 levels in the atmosphere, cause terrestrial plants to transpire less, thus lowering the amount of water they use – “less drop per crop”.    It, therefore, becomes evident that the impacts of climatic changes will have severe implications for food security in the future.

Uncertainty: a key challenge
The biggest challenge to the water resources community in modelling the impacts of a shifting climate on water resources is the extreme uncertainty associated with the exercise.  Apart, from the general well-known processes, how these shifts will affect water’s wider environmental interconnectedness still remains unclear.  In fact, the Intergovernmental Panel on Climate Change (IPCC) have taken a long time to properly include the effects of climate change on water resources into their annual reports, which is evidenced by only dedicating ten pages in their 4th Annual Report.  The reason for this has not been to downplay the importance of water, whose scarcity indeed was declared the second biggest global risk at the 2013 World Economic Forum, but simply because predicting the effects of climate change on water resources, continues to prove difficult, particularly on groundwater, where data is scarce.

The importance of stores
The effects of climate change on the global hydrological cycle may appear to only lead to situations of disadvantages.  However, studies from East Africa [3], which my Doctoral Research is grounded in, suggests that climatic effects in this part of the world, will cause an intensification in rainfall, which benefits groundwater recharge.  As research in the domain increases, so does the realisation that our understanding of groundwater resources remain limited.
Groundwater stores will become increasingly important in the future, as they possess a slower response-time to climatic shifts than that of surface water.  These resources, therefore, should be considered a key adaptation strategy to a shifting climate.  However, a history of legislative neglect of the resources, means that notions and understanding of sustainable management and utilisation of groundwater stores remain in their infancy.  Thus, it remains to be seen what the water the resources community has in store for the future.

[1] Rignot et al. (2011), Geophys. Res. Lett., vol. 38, L05503

[2] Nicholls and Casenave (2010), Science, vol. 328, 151 7-1520.

[3] Taylor et al. (2012) Nature Climate Change, Vol. 2, doi: 10.1038/nclimate1731