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  • My PhD project is looking at how the perspective of energy services can help us to identify what the best options are for domestic retrofit. Through this work I have made a focus on the metric of energy service efficiency and I am going to explain what this is, why it is important and specifically why it is important at a conference looking at energy efficiency in end use technologies.
  • As a guide, these are the areas that I’m going to cover in this presentationFirst I am going to explain what I mean by energy services when I use the term in this workI’ll then talk a bit about my motivation for this work I’m going to explain why this focus on the demand for energy services is importantI'm going to go through the metric of energy service efficiency that I've been using and that I cover in my paper and say a bit about how this could be used in the I'm going to finish by going through some of the potential applications of this work and then draw my conclusions
  • I’m going to start from what might be a slightly odd example and that is to talk to you about Coca-Cola, that brown sticky drink that seems to be absolutely everywhere these days.Now the Coca-cola company are clever. They started off selling a drink in 1886, but if you look at their advertising, they don’t really think that they’re selling a drink at all.Their latest advert shows their ‘sharing cans’ and here, there is no mention of drink at all. They’re selling friendship and ‘happy moments’. I mean, These are the people who invented Father Christmas! What I’m trying to say perhaps, is that coca-cola is no longer a drinks company – they are now a drink-service company, and they advertise not their drink, but the benefits people can get from their drink.
  • So I’m going to be talking about the concept of Energy Services and why this way of thinking is essential when we consider energy use in buildingsThe physical flows of electricity and gas are just energy carriers and should just be given the same level of concern as the bricks and glass in our buildings – they make it all possible but it’s only a niche group of people who actually count them. Most people just enjoy the buildings
  • In the same way, within buildings people just want the services: Thermal comfort, Illumination, Sustenance, Hygiene, Security, Communication, Entertainment, LuxurationForgive me if this is nothing new; the idea of energy services is certainly not new, but it’s by no means mainstream. Many people come across it in the context of ‘energy service companies’ which I’ll talk about a bit later, but these have moved towards being ‘energy companies that provide more services than just energy’ rather than ‘companies who sell “energy services” ‘ which is kind of where they started at.Of course it’s not only energy - electricity and fuels - that deliver services in homes and buildings, but other utilities such as hot and cold water or telecommunications. There is an EPSRC funded project led by my supervisor Julia Steinberger looking at the potential application of ‘Multi-Utility Service Companies’, MUSCos, and the work I’m doing with energy services would ideally stretch to covering all types of multi utility services Unfortunately, the term energy services is used to describe services around the delivery of utilities, such as consultancy, design of electrical and wiring work or energy efficiency assessments. It can also get tied up with referring only to energy service companies. The meaning I’m using is specifically the end benefits of the energy we use, or in the case of multi utility services, the end benefits of whatever utilities and flows go in.
  • When I started this project, I was interested in the business model of Energy Service Companies (ESCOs) or as they are in the UK – the business of Energy Performance Contracting (EPC). CLICK: In case anyone isn’t clear what these are, they offer a different approach to a typical utility company. A typical utility company sells a commodity, such as electricity and gas, to customers. They charge a price which is just above the cost they bought it for, and this margin is their profit. The more commodity they sell, the larger their profits. Therefore, although there are pressures on them to reduce the consumption of their customers, if they do this too well, their profits drop and the business doesn’t work.Energy Service Companies on the other hand enter into a mid to long term contract with a customer, guaranteeing to deliver the same level of service, but they can be creative in how they do this. By putting in energy efficiency measures, the amount of commodity, electricity and gas, that is required decreases and therefore the cost of this is lower. Some of the money saved can go towards paying for the capital equipment, and the rest can either be savings for the customer or profit for the ESCo, depending on the type of financial contract they agreed upon. Of course, savings on commodity mean that the same level of service is delivered with lower CO2 emissions.
  • CLICK: The name ESCo actually spans a broad spectrum of business models where the utility company offers some additional aspects as well as just selling the commodity. CLICK: Currently, they appear to be more on the side of selling energy efficiency measures than selling services and relying on measurement and verification to prove that they are delivering the results they are contracted to.CLICK: I wanted to explore the question of whether ESCOs could shift back to selling energy services to customers, taking away the need for a customer to buy kWh of electricity and gas and instead to pay for the services they require, with the aim that this could break the profit lock in of the traditional business model and that utility companies could help their customers to reduce the energy use of their buildings.CLICK: out of this aim, the questions which arose were: how do we measure service delivery? how do we compare negative impacts?If you want to sell services, you would need to have a way to measure services. We looked at the qualitative descriptions of residential energy services, and the existing quantitative measures didn’t quite seem to describe the whole service. This was our motivation for trying to develop alternative metrics for energy services.My motivation for this work is looking at how we are going to meet our carbon reduction targets in the buildings sector and specifically in residential housing as there is a step change required in how we deal with retrofits. Therefore, it is important to consider the whole energy chain from primary energy and materials to service delivered when comparing different options. CLICK: It is this environmental impact that I want to minimise, rather than cost, and the next step would be to work out what needs to be done to make the lowest impact options also the most financially viable – through carbon pricing, energy efficiency subsidies and boosting certain industries to bring down the costs of the most efficient technologies.
  • So, on to looking at the chain of energy that delivers energy service…So, typically, much of the attention given to the energy systemhas a strong supply side focusWe mine or drill to get our hands on primary energy and we combust or refine to get our hands on secondary energy carriers such as electricity, hot water and refined natural gas.Of course it’s not only drilling and mining that gets our secondary energy carriers – there’s a growing proportion coming from renewable sources. Overall this is definitely a good thing, but as this continues to grow we’ll find ourselves facing different challenges related to availability of critical materials and sources of biomass which don’t conflict with food crops and threaten the degradation of forests.We have great networks of distribution which deliver this energy to the point of use, where it is commonly called Final Energy.So as far as most considerations of the energy system are concerned, we just pump electricity and gas into houses and measure the rate at which we do this.But we know this isn’t actually the whole story…
  • But we know this isn’t actually what happens…We have set up systems within our houses and buildings which use this energy for good.In actual fact, we pack our homes and buildings full of technologies and appliances; boilers, washing machines, stoves, TVs, lights. These have been termed conversion devices, However, these aren't yet the energy services.Cullen and Allwood presented an interesting way to highlight the different roles of technologies within the system as shown here. They said that final energy is upgraded in conversion devices into useful energy – heat, motion or light. This useful energy is then degraded to low grade heat within passive systems – a room or an insulated refrigerator - in return for the delivery of energy services – a room at a comfortable temperature or satisfactory level of illumination when we are in it, or storage for the food the household requires.Thermal comfort, Illumination, Sustenance, Hygiene, Security, Communication, Entertainment, LuxurationOf course it’s not only direct energy that provides these services. We also benefit from ‘indirect energy’ or embodied energy in the materials, technologies, structures and other objects we use and waste in the process of delivering these services. And the energy used in transportation. Haas and Jonssonreferred to these as ‘indirect energy services’. Although technologies tend to be rated in terms of useful energy per final energy, this does not tell the whole story An approach by an energy service company to sell energy efficiency might recommend that the heating efficiency can be improved by replacing the exisiting boiler with a boiler with the same output but with a better efficiency. The same can be done with lights, air conditioning, ventilation, fridges etc. This achieves a technology delivering the same useful energy output with a lower requirement of final energy. However, with a broader look at the whole system, it may be found that an alternative approach can deliver the same energy service with a lower requirement of primary energy and a lower level of CO2 emissions or other environmental impact. It also allows the comparison of conversion devices and passive systems in combination with energy generation technologies.[Just for semantic clarification – I’m going to refer to technologies as the conversion systems or the passive systems, so the heater and the insulation]
  • So in theory, the idea of buying and selling energy services is quite a change from the current approach to the powering of houses and other buildings. To give the theory traction, it requires quantification. When trying to address the two points identified, of measuring energy service delivery and the negative impacts of the method of delivering the service, it was thought that an efficiency term was appropriate. Efficiency is a term used in many applications, but in generally it refers either to the amount of output gained from a given input or is an indication of the proximity of actual performance to an ideal performance. In order to measure the ability of different combinations of technologies to deliver energy services, I’ve been working with the concept of energy service efficiency. More accurately, I’m working with the idea of an energy service energy intensity which is just the inverse of an efficiency term. It is a measure of the energy input required to deliver an energy service.
  • Energy input was considered appropriate as a first measurement of environmental impact, although the type of energy input is important to bear in mind. When calculating the energy input, technologies and designs should be compared on an equal grounding, so the boundary over which energy is compared needs to be consistent.In the BREEDEM standard assessment procedure, boiler efficiency is rated as useful energy– over – energy delivered which only captures this point in the whole system. When comparing electric and gas heaters, there is a need to consider the chain from primary energy as plug electricity is less than 40% efficient.As mentioned earlier, the concept of ‘indirect energy’ services accounts for energy used in production and transportation – everything before the actual running of a technology. When this is taken into account we have the potential to compare, say, an electric resistance heater, … a wet radiator system with hot water derived from a … gas heater or … solar hot water collector, or … insulation. Included in life cycle analysis is the lifetime of the technologyThe type of input is also an important consideration. As well as “straightforward energy”, we should consider exergy – the quality of the energy, or potential to do work. Identifying the potential for low carbon energy to be used can improve the resulting CO2, but the full indirect energy input should be included. Energy input could then allow us to calculate other metrics such as consequential environmental impact or cost over lifetime of use.
  • Delivered Energy Service – I guess this is the difficult bit – defining what the service is.Typically, metrics have been used which don’t fully describe the service demanded as shown here. If the wrong metric is used, or demand for services isn’t addressed, more efficient but higher energy options appear more attractive due to oversizingAs previously mentioned, there’s no point in buying a huge fridge for 1 or 2 people if it’s far larger than necessary, or heating a whole house because per square metre of floor area it’s less energy therefore technically ‘more efficient’Conversely, the more accurate descriptions of services are more qualitative and this makes it difficult to accurately measure. When trying to measure service, Jonsson et al addressed the issues of comparative quality by breaking services down into volume, content, quality and motivation. They say that services should only be quantified to a point, and that qualification aspects will always be important. This could be built in by developing a matrix by which feasible comparative alternatives could be assessedHowever, for the comparison of technologies and design, quantification would be really valuable for progressing the energy service perspective. Service delivery should be broken down into a base unit: a ‘service unit’ similar to a ‘functional unit’ in lifecycle analysis, but addressing the service more closely to what people require. By, trying to measure this, or at least if we aim for sufficing rather than maximising, the potential for un-necessary over specification is reduced.
  • To use this theory and apply it to buildings, building energy performance models are useful tools, and through my work I am looking at how building models could be developed to best reflect the focus of energy services. I want to bring the energy service perspective into building energy performance models so that we can compare different systems of technologies, design and control in terms of energy service energy intensity and make recommendations for what the best design options are.If it is energy services we desire, then surely buildings should be designed to deliver energy services. Shouldn't we then assess energy performance based on the delivery of these services.Currently the Energy Performance Certificate rating on lighting depends on the percentage of energy saving bulbs in a building, but does that mean that a stairwell of a building lit to the level of a bright hospital waiting room with Compact Flourescent Lamps is performing well? Or a living room with 10 LED lamps is better than one with a single incandescent bulb – a slightly dubious example, and probably yes, but some consideration of appropriate illumination levels, and addressing the risk of rebound where more efficient bulbs are left on for longer, would enhance the current assessment procedure.Standard Assessment Procedures do take account of some control aspects such as whether there is separate heating control for different areas, but without properly understanding how the different options for service delivery work, it's difficult to imagine this being achieved on a greater scale
  • So to the conclusions:Unfortunately I don’t have the magic answer and the 10 step guide to applying this theory in practise… yet! But I do hope that this has given an interesting perspective on the way we consider our energy use. So to conclude…Energy services are the right perspective for considering the whole chain of energy use and energy efficiency in houses or buildings. Not just square metres of heated space, but for occupied space to be thermally comfortable. Not just litres of chilled storage, but food storage to suffice the current household. These are difficult metrics to pin downs, but important for understanding our demand for this whole energy systemFor each step in delivery, the efficiency of the stage is important, but is not the full story. We need to consider the whole system too and energy service efficiency is a proposed tool for doing just that. If this could improve our measurements of technology and building performance, that could be really useful for making sure in the future we are measuring the right things not just the easiest things. Too often, heating systems are considered simply by fitting the most efficienct conversion device without looking at the whole system more widelyIn a purely qualitative form, there isn’t the potential to incorporate these services into modelling of future cities, but quantification risks losing some of the integrity of the work. Perhaps there is still a way to bring these together.Typically, utility company business models make more money when their customers use more energy electricity and gas. Energy Service Companies can break this lock in and this work can hopefully help contribute to the development of this field. Imagine if instead of electricity and gas bills you could buy hours of thermal comfort or meal preparation in the same way you buy talk minutes and text messages. How would that look? Would you then actually be able to get the best available technology out to the masses? Could you address problems such as fuel poverty by ensuring that not gas, but thermal comfort, is affordable to all? If these companies are relying on the electricity, gas and other fuels they require to deliver the services being affordable into the future, surely the obvious answer is to move away from fossil fuels and towards more renewable generation where the cost is less volatile. I do think that it’s an important perspective to consider at every point of the energy chain so that at every point it is recognised that this is a link in the chain of a larger system
  • THANK YOU VERY MUCH for listening. I appreciate that we don’t have a huge amount of time for questions and feedback now, so if anyone has any comments of questions I’d be very greatful to hear them at this stage so please do catch me after of get in touch. thanks
  • THANK YOU VERY MUCH for listening. I appreciate that we don’t have a huge amount of time for questions and feedback now, so if anyone has any comments of questions I’d be very greatful to hear them at this stage so please do catch me after of get in touch. thanks
  • The Energy Service Concept has made its way out of academia through the application of energy service companies, ESCOs. In the UK these are marketed as energy performance contracts.The original idea was that an ESCo would identify the level of energy service a client is currently using and would guarantee to maintain that same level at the same cost. The more energy efficient the ESCo can make the building, the more money they save on utilities therefore their motivation for profit is the inverse of a typical utility company. They’d enter into this mid-to-long term contract and the client would benefit from security from increased bills, guarantee that the building would run properly, and often a more well kept building has the co-benefit of having a greater level of comfort generally. ESCos now span a broad range of companies and ESCOs, particularly the Energy Performance Contract vein of ESCOs, are arguably more about selling energy efficiency measures than selling services and relying on measurement and varification to prove that they are delivering the results they are contracted to.However, with better measurement, there would be more potential for selling services instead of utilitiesImagine if instead of electricity and gas bills you could buy hours of thermal comfort or meal preparation in the same way you buy talk minutes and text messages. How would that look? Would you then actually be able to get the best available technology out to the masses? Could you address problems such as fuel poverty by ensuring that not gas, but thermal comfort, is affordable to all? If these companies are relying on the electricity, gas and other fuels they require to deliver the services being affordable into the future, surely the obvious answer is to move away from fossil fuels and towards more renewable generation where the cost is less volatile. If it is energy services we desire, then surely buildings should be designed to deliver energy services. Shouldn't we then assess energy performance based on the delivery of these services.Currently the Energy Performance Certificate rating on lighting depends on the percentage of energy saving bulbs in a building, but does that mean that a stairwell of a building lit to the level of a bright hospital waiting room with Compact Flourescent Lamps is performing well? Or a living room with 10 LED lamps is better than one with a single incandescent bulb – a slightly dubious example, and probably yes, but some consideration of appropriate illumination levels, and addressing the risk of rebound where more efficient bulbs are left on for longer, would enhance the current assessment procedure.Standard Assessment Procedures do take account of some control aspects such as whether there is separate heating control for different areas, but without properly understanding how the different options for service delivery work, it's difficult to imagine this being achieved on a greater scaleAs well as the reactive case of assessing a building's performance, a better grasp of how different options for service delivery compare would inform householders or consultants as to the best options for design or retrofit in a proactive way.The energy service energy intensity metric could be multiplied by the level of service required to evaluate the energy requirement for comparing different system designs and comparing to the optimal achievable performance
  • As I keep sayingthis is not a new area and these are not points that haven't been worked through before, but there is certainly a lot of potential for work in this areaHowever we look, current ways of improving building performance, as in ‘the amount of energy we put in to run our buildings’, are not working well enough. These changes in approach to how we consider energy demand could be the shift we require.We need to aim for sufficiency of energy service demand and not always growth and maximisationWe need metrics to better describe the services people are requiringWe need to work out how to combine quantitative and qualitative aspects to enable the modelling potential of services We need to bring together Life Cycle Analysis data and understanding of what it is that different technologies can do
  • For fear of spoiling the ending, I’m going to start of with some of my conclusions

Transcript

  • 1. A Review of the Concept of Energy Service Efficiency as a Metric for Assessing the Provision of Energy Services in Residential Buildings Erica Marshall (Rici) University of Leeds Doctoral Training Centre in Low Carbon Technologies
  • 2. Structure □ Definition of Energy Services □ Motivation for this work □ Residential Energy Services □ Energy Service Efficiency □ Application to Building Energy Performance Models □ Discussion 2 Energy Service Efficiency : Erica Marshall 2
  • 3. Coca-cola Drinks Services 3 Energy Service Efficiency : Erica Marshall
  • 4. Energy Services E ER Y N G 4 Energy Service Efficiency : Erica Marshall
  • 5. Energy Services a comfortable thermal environment E ER Y N G the illumination of a work space clean clothes warm meals mobility for people and goods tables, and other real things 'Energy services are the benefits that energy carriers produce for human well being' (Modi et al. 2005) 'Energy demand, paradoxically, is not driven by a demand for energy itself, but rather by a demand for energy services' (Steinberger et al. 2009) 'Energy services are important building blocks in forming a lifestyle to provide welfare.' (Norgard 2000) 5 Energy Service Efficiency : Erica Marshall
  • 6. Motivation □ Energy Service Companies (ESCOs) and Energy Performance Contracting (EPC) approach Sel l i ng ener gy ser vi ces Question: M ng ener gy aki ef f i ci ency af f or dabl e how could you better shift back to selling services? Questions identified: how do we measure service delivery? how do we compare negative impacts? Further interesting Question: how do we make lowest impact option financially viable? 6 Energy Service Efficiency : Erica Marshall 6
  • 7. Motivation □ Energy Service Companies (ESCOs) and Energy Performance Contracting (EPC) approach Sel l i ng ener gy ser vi ces Question: M ng ener gy aki ef f i ci ency af f or dabl e how could you better shift back to selling services? Questions identified: how do we measure service delivery? how do we compare negative impacts? Further interesting Question: how do we make lowest impact option financially viable? 7 Energy Service Efficiency : Erica Marshall 7
  • 8. Residential Energy Services Pr i m y Ener gy ar Secondar y Ener gy 8 Energy Service Efficiency : Erica Marshall Fi nal Ener gy 8
  • 9. Residential Energy Services Passive System Final energy Electricity Gas Diesel Conversion Device Boiler Light filament Useful Energy Heat Motion Light Low Grade Heat Energy Services 9 Energy Service Efficiency : Erica Marshall 9
  • 10. Energy Service Efficiency Metric I often say that when you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind; it may be the beginning of knowledge, but you have scarcely in your thoughts advanced to the state of Science, whatever the matter may be." Delivered Energy Service Energy Input Energy Service Energy Service - Lord Kelvin = = Energy Input Energy Intensity Efficiency Delivered Energy Service 10 Energy Service Efficiency : Erica Marshall 10
  • 11. Energy Service Efficiency Metric Energy Input Energy Service = Energy Intensity Delivered Energy Service Considerations: □ Energy Chain □ Full Life Cycle □ Type of Input 11 Energy Service Efficiency : Erica Marshall Energy Services 11
  • 12. Energy Service Efficiency Metric Energy Input Energy Service = Energy Intensity Delivered Energy Service Current metrics of services Qualitative descriptions of services kg food cooked Litre chilled space 'to keep the occupants of the house adequately fed and watered' m2 floor area 'to have spaces of the house at a comfortable temperature and condition when occupied' 12 Energy Service Efficiency : Erica Marshall Litre hot water m2 cleaned area kg clothing 'to maintain the occupants of the house, possessions and the house itself at an adequate level of cleanliness and hygiene' m2 illuminated area Lumens 'to have the space of the house at a sufficient level of illumination for the task undertaken when occupied' Bytes Hour of operation 'to enable the occupants to spend their leisure time in a way which they find enjoyable' 12
  • 13. Building Energy Service Performance Models Building Design What is the best system of technologies, design and control … …for delivering energy service in a certain building? (new or retrofit) Building Energy Performance If energy service are what people demand… …could we rate buildings according to the delivery of services? 13 Energy Service Efficiency : Erica Marshall 13
  • 14. Conclusion • We need to have a demand side focus and services are the key demand • Energy Service Efficiency metric would be valuable • Modelling requires quantitative inputs and outputs which has always been difficult for energy services and easier for supply side accounting • Improve potential for alternative business models where more profit can be made from less energy use and less negative impact • Optimise whole system and not just each link 14 Energy Service Efficiency : Erica Marshall 14
  • 15. Thank You Any questions, recommendations, points for discussion? Erica Marshall (Rici) pmecm@leeds.ac.uk #RiciMarshall 15 Energy Service Efficiency : Erica Marshall 15
  • 16. References Modi, V., S. McDade, D. Lallement, and J. Saghir. (2006). Energy and the Millennium Development Goals. New York: Energy Sector Management Assistance Programme, United Nations Development Programme, UN Millennium Project, and World Bank. Steinberger et al. (2009). Profiting from negawatts: Reducing absolute consumption and emissions through a performancebased energy economy. Energy Policy, 36(1), 361-370. Nørgård, J.S. (2000). Models of energy saving systems: the battlefield of environmental planning. International Journal of Global Energy Issues, 13, 102-122 Cullen, J.M. & Allwood, J.M. (2010). The efficient use of energy: Tracing the global flow of energy from fuel to service. Energy Policy, 38(1) 75-81. Haas, R. et al. (2008). Towards sustainability of energy systems: A primer on how to apply the concept of energy services to identify necessary trends and policies. Energy Policy, 36(11) 4012-4021. Jonsson, D.K. et al. (2011). Energy at your service: highlighting energy usage systems in the context of energy efficiency analysis. Energy Efficiency, 4(3) 355-369. Many more references in accompanying paper Pictures: National Coal Mining Museum - a pen drawing painting by John W ... www.jwjonline.net More Drilling Won't Lower Gas Prices: Soaring Domestic Production ...livinggreenmag.com Watercolour sketch of Eggborough power station cooling towerscambridgeartacademy.com Carmarthen Artist: April 2011carmarthenartist.blogspot.com climatewww.climateandfuel.com Wind: Sunset Wind | Marie Wise, Fine Artistwww.mariewise.com Solar Panel House Stock Vector Illustration And Royalty Free Solar ...www.123rf.com Water | Home Improvement Information | Find Home Improvement ...www.homeimprovement411.org 16 Energy Service Efficiency : Erica Marshall Probing Question: What heats the earth's core?phys.org http://images.fineartamerica.com/images-medium-large/prettyboydam-john-d-benson.jpg Trimble - Oil, Gas and Chemical - Transportationwww.trimble.com Igorij's "Sketch and Line Art (Clip-art)" set on Shutterstockwww.shutterstock.com small and heartfelt: April 2009smallandheartfelt.blogspot.com Wooden-Toys-Direct - KidKraft, kinder kuche, puppenhaus, Kidkraft Puppenhaus, KidKraft Kinder Kuchewooden-toys-direct.co.uk andrea joseph's sketchblog: June 2011andreajoseph24.blogspot.com DIY Kitchenette - A Beautiful Messwww.abeautifulmess.com Drawing | Wild Yorkshireblog.wildyorkshire.co.uk Debbie Miller Painting: January 2009debbiemillerpainting.blogspot.com 16
  • 17. Conclusion • When considering energy system, we need to have a demand side focus and services are the key demand • As the concept of Energy Services becomes mainstream, we need to have a common understanding of what it means • We need to ensure we have a thorough understanding of how technologies contribute to delivering energy services • Modelling requires quantitative inputs and outputs which has always been difficult for energy services and easier for supply side accounting • Energy Service Efficiency metric would be valuable for this 21 Energy Service Efficiency : Erica Marshall