The energy consumed by ICT Marco Ajmone Marsan

Transcription

1 The energy consumed by ICT Marco Ajmone Marsan Politecnico di Torino, Italy IMDEA Networks Institute, Spain

2 OUTLINE Energy trends The ICT role Cellular networks Sleep modes Renewable sources Policy matters Marco Ajmone Marsan 2

3 TREND: The FP7 Network of Excellence on Green Networking Towards Real Energy-efficient Network Design

4 The Problem Energy is becoming the issue of our future o Energy production with fossil fuels causes GHG emissions which produce climate changes o Energy is becoming expensive Energy efficiency is a goal in all sectors, ICT and networking included Marco Ajmone Marsan 4

5 Fossil fuel prices Energy price is growing Source: Trends to 2050, European Commission. Marco Ajmone Marsan 5

6 Electricity prices Electricity price is also growing in the next 10 years Source: Trends to 2050, European Commission. Marco Ajmone Marsan 6

7 Electricity demand Electricity demand is growing Source: Trends to 2050, European Commission. Marco Ajmone Marsan 7

8 Electricity generation Energy from renewable sources will grow Source: Trends to 2050, European Commission. Marco Ajmone Marsan 8

9 What about ICT? Information and Communication Technologies (ICT) play a positive role for energy efficiency: moving bits instead of atoms intelligent transport systems teleworking and telecommuting e-commerce electronic billing new manufacturing systems sensors to monitor and manage our environment smart buildings, neighborhoods, cities Marco Ajmone Marsan 9

10 What about ICT? ICT will allow savings of the order of 25-30% in manufacturing 20-30% in transport 5-15% in buildings for a total of about 17-22% Moreover, ICT is expected to significantly improve the energy generation, transport and utilization through the adoption of Smart Grids Source: Ad-hoc Advisory Group ICT for Energy Efficiency of the European Commission DG INFSO, Marco Ajmone Marsan 10

11 However, ICT is also part of the problem ICT energy consumption is huge and increasing ICT category electricity use (TWh/y) Total worldwide electricity use CAGR 2.9% 1-1.5% of total Networks CAGR 10.4% PCs CAGR 5.1% Data centers CAGR 4.4% The CAGR value is the compounded annual growth rate over the 2007 to 2012 time frame Total worldwide electricity use (TWh/y) network consumption faster than other sectors Source: TREND Final Deliverable on Assessment of power consumption in ICT, 2013 and S. Lambert et al., Worldwide electricity consumption of communication networks, Optics Express, Vol. 20, No. 26, Marco Ajmone Marsan 11

12 Traffic growth number of devices grows (new markets) new and more traffic intensive services Source: Cisco VNI, Marco Ajmone Marsan 12

13 The case of mobile networks The mobile industry sums to 0.5% of global emissions Electricity cost is up to 70% of mobile operators OPEX! Radio access networks are the prime target for energy saving Source: S. Vadgama and M. Hunukumbure, Trends in Green Wireless Access Networks, IEEE ICC Marco Ajmone Marsan 13

14 Traffic growth will make it worse Mobile network traffic is expected to grow by an order of magnitude in 5 years!!! n n Larger no. of devices (new markets) More traffic intensive services Source: Cisco VNI Mobile, Marco Ajmone Marsan 14

15 Which segment of the network? Terminals: Already energy-efficient by design Core devices: Energy-hungry Not many Very critical Handle aggregate traffic Marco Ajmone Marsan 15

16 Which segment of the network? Access network: Energy-hungry Many devices Some redundancy Less critical than core devices Very close to the user, hence high traffic variability Marco Ajmone Marsan 16

17 Mobile networks According to an estimate of Nokia Siemens Networks, worldwide 3 billion x 0.1 W = 0.3 GW 3 million x 1.5 kw = 4.5 GW 10,000 x 10 kw = 0.1 GW Marco Ajmone Marsan 17

18 Energy efficient solutions Traditionally, little attention to consumption in the design of the devices and of the network Many inefficiencies derive from the combination of little load proportionality of consumption due to traffic variability, long periods under low to medium load Weekday Weekend power Pidle>>0 Traffic, f(t) Inefficiency 0.2 Psleep 0 load 0 00:00 05:00 10:00 15:00 20:00 00:00 Time, t [h] Marco Ajmone Marsan 18

19 Energy efficient solutions Consume energy for capacity deployment, not for capacity usage Many solutions try to make capacity adaptive to load Use of sleep modes for the BSs Network sharing Resource on demand architectures Saving of up to 50% can be achieved, Marco Ajmone Marsan 19

20 Planning and dimensioning: long time scales peaks Daily traffic profile in a segment lunch night high capacity to carry all the traffic over-provisioning: waste of capacity

21 Sleep modes of devices or portions of the network Due to natural traffic variability, the network is over-dimensioned and wastes energy for long periods of time Adapt capacity to actual traffic needs by putting to sleep mode devices or portions of the network when traffic is low

22 Network planning with sleep modes Since energy consump9on only marginally depends on load, over-provisioning à waste of energy peaks define planning peak scheme Adapt capacity to traffic by using sleep modes off-peak scheme Michela Meo Politecnico di Torino

23 Network sharing Several compe&ng mobile operators cover the same area with their equipment Networks are dimensioned over the peak hour traffic During low traffic periods the resources of one operator are sufficient to carry all the traffic Make operators cooperate to reduce energy consumption Michela Meo Politecnico di Torino

24 Network sharing n In turn, q Switch off the network of one operator, when traffic is low and the ac9ve operators can carry all the traffic q Let users roam to other operators q Balance costs Source: M. Meo, M. Ajmone Marsan. Energy efficient wireless Internet access with cooperative cellular networks. Computer Networks, Volume 55, Issue 2, February 2011, Pages Michela Meo Politecnico di Torino

25 Case study: Some European Countries Country MNOs Market share [%] Subscr. [M] France Germany Greece Italy Netherlands Poland Portugal Spain Romania Russia Ukraine U.K

26 Case study: Some European Countries consumer, const consumer, var business, const business, var France Germany Greece Italy Netherlands Poland Portugal Spain Romania Russia Ukraine UK Relative saving

27 Energy efficient solutions Consume energy for capacity deployment, not for capacity usage Many solutions try to make capacity adaptive to load Use of sleep modes for the BSs Network sharing Resource on demand architectures Saving of up to 50% can be achieved, is this enough? Marco Ajmone Marsan 27

28 Micro and macro effects of energy efficiency Jevons paradox: Increase of energy efficiency to produce a good/service reduces cost of the production and, hence, its price increases the demand increases the energy consumption Marco Ajmone Marsan 28

29 From energy efficient networking to sustainable networking n Energy efficiency is good since, through cost reduction, it leads to q q q Higher production à better quality of life for more people Reduction of price increase and energy shortage Global environmental advantage if coupled with green taxes to keep the price constant n but, for sustainability, it must be coupled with new energy generation principles (RES Renewable Energy Sources) Marco Ajmone Marsan 29

30 Powering BSs with renewables n Zero grid-electricity Networking (ZEN) BSs rely purely on renewable energy sources and are not connected to a power grid q q q Can acquire limited amounts of energy from (intermittent) local generators exploiting renewable sources Any energy surplus is stored in a battery The BS can operate also in periods of low or no production, as long as energy is available, but it is forced to switch off when the battery is depleted n Hybrid systems that, when battery is depleted, rely also on the power grid (or a secondary generator) Marco Ajmone Marsan 30

31 Powering BSs with renewables n Power BSs with Renewable Energy Sources q To deploy networks where the power grid does not exist, is not ubiquitous or is not reliable q To achieve extremely low carbon footprints q To reduce operational cost q To survive to power grid outages or natural disasters which damage the power grid Possible scenarios: 1. New opportunities for the deployment of networks in emerging regions Marco Ajmone Marsan 31

32 Possible scenarios: Emerging areas Marco Ajmone Marsan 32

33 Possible scenarios: Emerging areas bad grid off-grid Expected expansion of mobile networks in rural regions in Africa and Asia Most of the BSs are powered with diesel generators Costly (especially due to fuel transportation) Bad for the environment Source: Green Power Design Approach and Feasibility Analysis, Green power for Mobile Technical White Paper, Aug Marco Ajmone Marsan 33

34 Possible scenarios: Emerging areas bad grid off-grid Renewables can be convenient n Cost reduction n n Environmental concerns Political issues (related to energy supply) In India, about 400,000 BSs 75% of rural sites and 33% of urban sites on RES by 2020 Source: Green Power Design Approach and Feasibility Analysis, Green power for Mobile Technical White Paper, Aug Source: K. Tweed, Why Cellular Towers in Developing Nations are Making the Move to Solar Power, Scientific America, 15 Jan Marco Ajmone Marsan 34

35 ZEN Zero grid-electricity Networking n Power BSs with Renewable Energy Sources q To deploy networks where the power grid does not exist, is not ubiquitous or is not reliable q To achieve extremely low carbon footprints q To reduce operational cost q To survive to power grid outages or natural disasters which damage the power grid Possible scenarios: 1. New opportunities for the deployment of networks in emerging regions 2. New business models (high electricity price, green incentives and environmental awareness) 3. Dense urban areas where cabling is a problem 4. Critical infrastructure protection 5. Marco Ajmone Marsan 35

36 Pure PV (ZEN) Marco Ajmone Marsan 36

37 Hybrid PV-Grid Connect to the Power Grid to reduce size of PV panel & number of batteries Marco Ajmone Marsan 37

38 Hybrid PV-diesel Use diesel instead of the grid as a backup Marco Ajmone Marsan 38

39 ! Figura 28: Radiazione solare annuale in Europa (Fonte: PVGIS, Institute for Energy - Unione Europea, 2012) Two locations Solar radia9on Torino! (medium: 4 kwh/m2, high seasonal varia9ons) Solar radia9on Aswan! Figura 29: Radiazione solare annuale in Africa (Fonte: PVGIS, Institute for Energy - Unione Europea, 2012) (high: 6.8 kwh/m2, low seasonal varia9ons)!! H`!! Figura 28: Radiazione solare annuale in Europa (Fonte: PVGIS, Institute for Energy - Unione Europea, 2012) Marco Ajmone Marsan 39

40 Real traffic profile Traffic grows according to 50% Compound Average Growth Rate (CAGR) Focus on LTE, with initial low traffic load (0.02) due to start-up of the new technology and maximum (0.75) in 10 years Source: Cisco Visual Networking Index: Global Mobile Data Traffic Forecast Update, , Marco Ajmone Marsan 40

41 Real traffic profile 1 Weekday Weekend 1 Weekday Weekend 0.8 business 0.8 residential Traffic, f(t) Traffic, f(t) :00 05:00 10:00 15:00 20:00 00:00 Time, t [h] 0 00:00 05:00 10:00 15:00 20:00 00:00 Time, t [h] Traffic grows according to 50% Compound Average Growth Rate (CAGR) Focus on LTE, with initial low traffic load (0.02) due to start-up of the new technology and maximum (0.75) in 10 years Source: Cisco Visual Networking Index: Global Mobile Data Traffic Forecast Update, , Marco Ajmone Marsan 41

42 Total cost in 10 years Hybrid is always cheaper than pure diesel Pure PV saves from the 5 th year wrt pure diesel Torino Hybrid saves from the 8 th year wrt the grid-only case Marco Ajmone Marsan 42

43 Selling back energy Total cumulative cost, with the possibility to sell back energy Save from the 6 th year Marco Ajmone Marsan 43

44 Conclusion and discussion Awareness about the huge energy consumption of communication networks has led to development of more energy efficient solutions and technologies However, for sustainability, energy efficiency alone is not enough Marco Ajmone Marsan 44

45 Conclusion and discussion Networking should be combined with new energy generation principles Powering BS with renewable sources is cost effective allows service provisioning in disadvantaged areas is well suited to critical infrastructure protection allows communications after natural disasters avoids cabling difficulties Marco Ajmone Marsan 45

46 Policy matters Recommend energy reduction targets for European MNOs (and manufacturers) Identify adequate metrics power power/throughput power/(throughput*area) power/(throughput*area*users) Specify minimum fraction of RES Facilitate resource (network) sharing Better energy efficiency in coverage-limited areas Better energy efficiency in capacity-limited areas Marco Ajmone Marsan 46

47 Thank you! Questions? Marco Ajmone Marsan 47