AC/DC - History and Differences http://www.youtube.com/watch?v=GpaVgUfiOXo VJ7 Nikola Tesla (1856 - 1943) Thomas Alva Edison (1847 - 1931) https://www.youtube.com/watch?v=NoKi4coyFwO Induction Motor The AC power supplied to the motor's stator creates a magnetic field that rotates in time with the AC oscillations. The rotating magnetic flux induces currents in the windings of the rotor Induction Motor Production of Electricity Direct vs. Alternating curent http://www.pbs.org/wgbh/amex/edison/sfeature/acdc.html Production of Electricity • Direct current (DC) 0 Electrons flow only in one direction in a closed circuit, ie. DC has zero frequency 0 The electrons in the circuit flows from "-" to "+" 0 To get the energy of an electron to the appliance the electron must complete the way from source to the appliance 0 For longer routes (eg. already from 1 km) DC quickly loses its power and leads to huge losses in networks Battery Circuit What is the use? Copyright ^ Z0O4 www.rriakeitsolar.coiti AH rights reserved. Production of Electricity Direct current (DC) 0 It is used all around us, for example in batteries, rechargeable batteries, chargers, adapters, thermocouples, solar cells, transistors, etc.. 0 But even in trams, trains in the region Decin-Praha-Ostrava, in the train operation in the world, in most of the world's subways, etc..) 0 It is also used by remote transmissions of large volumes of electricity, so called HVDC lines. The advantage is that it can interconnect systems on different frequencies as well as asynchronous systems 0 With very high voltages DC is more efficient at transporting electricity than alternating current ° However the changing of the voltage is complicated and expensive, and therefore a high-voltage DC power supply is used only during transportation over long distances (more than 600 km for overland lines). 0 In practice the HVDC is used when connecting remote sources (typically dams and other renewable sources), or when connecting electrical systems with different frequency alternating current. 0 "Natural" sources of DC are basically any non-rotating power plants (battery, solar cells, dynamo - exemption) Production of Electricity Production of Electricity • Alternating current (AC) 0 Electrons flowing back and forth, volatile, periodically alternating 0 In normal network frequency of 50 Hz the current changes direction every 10 milliseconds 0 Electricity is produced in the form of a sine curve 0 Electrons almost do not wander through the conductor, they tap into the neighboring electron and passes its charge, so it gets from the source to the appliance ° They move with much shorter routes, leading to significantly lower losses in the network Voltage Direct current What is Alternating current the use? 7 Time Figure 1 Production of Electricity Alternating current (AC) ° The main advantage of AC versus DC is easy increase and decrease of voltage and much cheaper industrial production and distribution 0 It is used in mass production of electricity and for the transmission of power at a greater distance, withsignificantly lower losses that are achieved using higher voltages ° High voltage transport lines are used for remote supplies using easily transformable alternating current. 0 Very simple transformers are used for change in voltage, which consists of two coils wound around a common magnetic core. The proportion of the incoming and outgoing voltage is proportional to the proportion of the number of coil windings. 0 The sources are all rotating motors, dynamos and nowadays mainly structurally simpler alternators ° The disadvantage of AC is the need to maintain a stable frequency network (ie synchronize all connected generators). Production of Electricity Star wiring, phase conductors Delta wiring, stranded (composite) conductors Production of Electricity http://power.apitech.com/engineering-tools.aspx Production of Electricity Types of plugs/sockets in the world Types of plugs/sockets in the world North America North Amenta North America North America UK (NEMA6-2Ü) (NEMAL6-20) (NEMA5-15) (NEMA5-20) (BS1363/A) lt-, Type A Type B Type C Type D Type E Type F Type G Type H Type I Type J Type K Type L Type 11 IEC 320 WM WA-5 WA-9C WA-10 WA-9 WA-9 WA-7 WA-14 WA-16 WA-11A WA-20 WA-12 WA-10L WA-320 ^^^^^b^blNfr * id*. > * WE-106 WE-105 WE-109C WE-110 WE-109 WE-109 WE-107 WE 114 WE-116 WE-111 WE-120 WX-112 WE-110L WE-320 v.m>-<*«€> ^iiiJt% Production of Electricity HVDC Interconnection by ABB Long distance bulk transmission allows for stable, reliable transmission of more power across great distances and geological barriers with less environmental impact than traditional HVAC. Planned Future HVDC Projects by 2020 in China (The year means project in operation) Irkutsk (Russia) - Beijing 800kV. 6400 MW. 2015 Ni 135 Hami - C. China_ ÓÓÓkV, 6400 MW, 2018 Humen Xianjiaba - Shanghai 800kV,6400 MW, 2011 Xiluodu - Hanzhou 800kV, 6400 MW, 2015 Xiluodu - Hunan , 6400 MW, 2014 Jinsha River II - East China 800kV, 6400 MW, 2016 Jingping - East China 800kV, 6400 MW, 2012 Jinsha River II - East China 800kV, 6400 MW, 2019 Jinsha River II - Fujian 800kV, 6400 MW, 2018 Nuozhadu-Guangdong 800kV, 5000-6000 MW, 2015 BtB China-Russia (HciHc) |; 750 MW, 2008 FarEast (Russia) - NE Chin; 3000 MW, 2010 Humeng - Liaoning 800kV, 6400 MW, 2018 Hulunbeir (Inner Mongolia) Shenyang_ 3000 MW. 2010 BtB Northeast-North (Gaoling) 1500 MW. 2008 North Shaanxi-Shandong 3000 MW. 2011 BtB Shandong - East 1200 MW, 2011 BtB North - Central 1000 MW, 2012 ezhouba-Shanghai Expansion 3000 MW, 2011 ingbao BtB Expansion 750 MW, 2009 Goupitan - Guangdong 3000 MW. 2016 Yunnan - Guangdong 3000MW, 2013 800kV, 5000 MW, 2009 Bangkok 4. J0l2|Sí«íel2 ABB (Indicatrve m«p) Transfer and Distribution of Electricity The power system involves a process of electricity generation from different types of primary sources (fossil fuels, hydropower, wind, geothermal, nuclear, solar), qualitative transformation of the electric energy, transmission and distribution, and end use. All these processes are carried out through the electricity grid (transmission, distribution). They are dynamic - at any time must equal the energy consumed energy produced. Electrical energy is only a transitional form, it soon turns into light, heat or mechanical. The transmission system (transmission, distribution) is a set of interconnected devices that allow the transmission of electrical energy from the source to the consumer Transfer and Distribution of Electricity The power system is an interconnected set of equipment for the generation, transmission, transformation and distribution of electricity, including electrical connections and direct lines, systems and metering, protection, control, security, information technology and telecommunications. • The power system has several parts, namely: production power stations network power lines Transfer and Distribution of Electricity Electric power plants are installations that convert any energy into electricity. Electric stations is a complex of buildings and equipment, which enables the transformation, compensation, conversion or transmission and distribution of electricity, including the resources necessary to ensure their operation. Electric stations are transformer stations (used to change the voltage of electricity at the same frequency and its distribution), switching station (serving the same distribution of electrical energy without voltage transformation and without conversion), converter stations (used to convert the type of voltage or frequency) and compensating stations (used to compensate reactive components of alternating current, or line parameters). Power grid/lines is an important part of every device and allows transmission of electrical power and signals over distance. Electrical wiring is formed by conductors which serve to conduct electrical current and insulation separating the living part from the environment (except for bare lines). We distinguish four kinds of electric lines: lines of bare conductors (mainly outside), lead in pipes and rails, bridge line of wire and cable management. Transfer and Distribution of Electricity Transfer and Distribution of Electricity IT Tlr< Switching station Transformer station Transformer 30864882 Transfer and Distribution of Electricity Transfer and Distribution of Electricity L1 L2 L3 N Vlastní spotreba Transformátor L1 L2 L3 Transformátor Přenosová / distribuční soustava Místní soustava L1 L2 L3 N PE Každých 50 metrů Uzemnění Transfer and Distribution of Electricity The produced electricity must be transported to the place of consumption, according to Kirchhoffs laws electricity has the advantage that it does not need any energy to this movement, because electricity flows naturally from higher voltage to lower voltage points. To change the voltage in electric power systems the transformers are used. Electricity thus enters the high-voltage transmission (parent system), then it is transformed to a lower voltage distribution systems (grid) and then to low voltage (local system). Electricity is eventually distributed either by phase conductors or stranded conductors. Materials for outdoor or cable wires are copper cables and wires (best electrical and mechanical properties, high resistance to external influences, but the high price and exceptional use), or Al, Fe or Al alloys, bronze and steel Transfer and Distribution of Electricity Primární vinutí Np závitů Primární proud Sekundární vinutí Ns závitu Sekundární ls proud Transfer and Distribution of Electricity Electric lines are part of the grid. It is a set of interconnected power stations and lines for the transmission and distribution of electric energy. AC lines □ UHV(800+kV) □ EHV(230-800kV) □ HV (69 kV to 230 kV) □ MV(0,6-69kV) □ LV (50 V-600 V) □ ELV (less then 50 V) Transmission Transmission Transmission/Distribution Industrial/Distribution Local Transfer and Distribution of Electricity Transported Capacity in Electric Grids Voltage Transported capacity 230/400 V 3,55 kWe 22 kV 10,76 MWe 110 kV 268,9 MWe 220 kV 1 075 MWe 400 kV 3 555 MWe Source: „Elektroenergetika //'n.d., s. 5. Transfer and Distribution of Electricity Transfer and Distribution of Electricity 2 ■ i s e Transfer and Distribution of Electricity Transfer and Distribution of Electricity Transfer and Distribution of Electricity L1 L2 L3 N Vlastní spotreba Transformátor L1 L2 L3 Transformátor Přenosová / distribuční soustava Místní soustava L1 L2 L3 N PE Každých 50 metrů Uzemnění Pricing and Market Factors influencing the price of electricity production Supply Side Demand Side • Production capacity • Macroeconomic factors • Capital expenditures (CAPEX) • Weather through depreciation • Operational expenditures (OPEX) • Fuel • Emission Allowances • Weather • Hydrology • Wind • Temperature • Global price of energy (oil) Source: Next Finance (2007): Trh s elektrickou energií v Evropě, Praha, dostupné on-line (http://www.pxe.cz/pxe_downloads/lnfo/pxe_analyza.pdf), s. 5; adjusted by T. Vlček Merit Order Effect (MOE) • way of ranking available sources of energy, especially electrical generation, based on ascending order of price together with amount of energy that will be generated • marginal costs of production reflect the order • those plants with the lowest marginal costs are the first ones to be brought online to meet demand, and the plants with the highest marginal costs are the last to be brought on line (ä Öko-Institut e.V. How supply and demand determine electricity prices The merit order principle 120 ,1 (/> — 0 t; Ü o 1 n 100 E E ■ CO E 0) a tr o (A 3 UJ £ 20 Power plant capacity last pov/ar plant utilized to fulfill demand »x« power plants utilized to meet demand »x« power plants not needed to.fulfil demand »x« demand »xx at a specific tune O renewable energies ■ @ nuclear power ■ Q lignite ■ O hard coal Q natural gas ■ (§) heating oil SOURCE OEKO-INSTITUT. 2013 Illustrating electricity price fluctuations due to the Merit Order Effect CL 1 E W J 1 Operating costs (Euro/MWh) Power Demand Higher prices for electricity are... Electricity prices are reduced... ...associated with low input from renewables Renewables Nuclear Lignite Hard Coal Natural Gas Oil Capacity (GW) ...with higher input from renewables Renewables Nuclear Lignite Hard Coal Natural Gas Oil Capacity (GW) © BY SA 4.0 Merit Order Effect (MOE) • Are RES good or bad? Customer's point of view - Electricity price dropped considerably - Higher competitiveness for industry vs. support of RES paid by both Producer's point of view - Lower revenues - Deformed investment environment - New market opportunities vs. loss of market Merit Order Effect (MOE) Historické ceny ročních CZ base kontraktů / Historical Prices of CZ Base CALs 50,00 45,00 40,00 CAL-15 — CAL-16 v.. CAL-17 CAL-18 Mm. CAL-19 5 UJ 35,00 30,00 25,00 20,00 15,00 o (M O (M O (M O (M O (M O (M O (M O (M O (M O (M O (M O (M O (M O (M O (M O (M O (M O (M O (M O (M O (M O (M O (M O (M t- CO CJ> t- t- CJ> t- t- CJ> t- t- Source: PXE Merit Order Effect (MOE) Electricity price is determined by the most expensive plant. 1,000 MW coal or nuclear makes no difference for the market. Nuclear does not equal cheap electricity for the consumer, only sufficient generating capacity equals cheap electricity! Pricing and Market - Consumers • In a liberalized market the final price of electricity consists of the price of electricity (commodity) and a number of regulated components that reflect the naturally monopolistic character, such as transmission and distribution. • Also the support for RES is among the price components. • The regulated components are set by the Energy Regulatory Office. Pricing and Market - Consumers o Share of price components for electricity supply to households in 2010 and 2014 Electricity incl. margin 42,27 % 30% Market operator 0,12% 0,2 % System services of CEPS 3,94 % 2% Renewables, cogeneration and decentralized sources 4,41 % 10% Electricity distribution and transport 31,86% 40,2 % Ecological tax 0,72 % 0,6 % VAT 16,67 % 17% Source: Energetický regulační úřad Pricing and Market - Consumers o The development of contribution to the RES, CHEP and DS for end consumers Year 2009 2010 2011 2012 2013 2014 2015 2016 Contribution in CZK per 1 MWh 52,18 166,34 370,00 419,22 583,00 495,00 495,00 495,00 Regulation of Electricity Flows • The power system is dynamic, permanently active, and within seconds changing system. •Currently, it is optimized for 50 Hz frequency. •In this network frequency, the generated active power (which is equal to the sum of active power producing generators throughout the system) is just equal to consumption (sum of inputs of all appliances and network losses). •The balanced supply of electricity and its consumption is the optimum state of the network. •Negative symptoms: worsening power quality (frequency reduction), overvoltage, undervoltage networks, brownout, blackout, island operation •The reasons for the emergence of those conditions are different from planned and unplanned shutdowns of generating units, through unexpected damage to transformers, substations and networks, the consequences of the current weather conditions (eg. heavy snowfall, the sharp drop in the outdoor temperature, etc.), or changes in electricity production from renewable resources (ie., wind and solar power). •These conditions are prevented by regulatory backups Baseload vs. Peakload VYTVÁŘENÍ REGIONÁLNÍCH TYPOVÝCH DIAGRAMŮ tiii i i i i i i i i i ii i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i * i i i i i i i i i i i i r 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 53 3 5 7 9 11 13 Týden Regulation of Electricity Flows Simplified Chart of Regulatory Backups of ČEPS, a.s. Systém Service Code Timframe Description Regulátory Backup - Seconds (Regulační záloha vteřinová) RZV 30 seconds Primary regulation Regulátory Backup - 15 Minutes (Regulační záloha dosažitelná do 15 minut) RZ15 15 minutes Secondary regulation, sources with 10 and 15 minutes start-uptime Regulátory Backup - 30 Minutes (Regulační záloha kladná dosažitelná do 30 minut) RZ30+ 30 minutes Tertiary positive regulation (dispatch regulation, load adjustment, import) within 30 minutes Negative Regulátory Backup - 30 Minutes (Regulační záloha záporná dosažitelná do 30 minut) RZ30- 30 minutes Tertiary negative regulation (dispatch regulation, load adjustment, import) within 30 minutes Regulátory Backup - 30+ Minutes (Regulační záloha (netočivá) dosažitelná v čase delším než 30 minut) RZN>30 30+ minutes Regulatory dispatch backup, import, within 30+ minutes Source: ČEPS, a.s. (2010): Roční příprava provozu na rok 2011, Praha, ČEPS, a.s., on-line text (http://www.ceps.cz/doc/soubory/20101203/RPP_2011.pdf), s. 4.P3. Výběr a úprava T. Vlček. Regulation of Electricity Flows https://youtu.be/9Fi-eu4IQMo?t=5m5s I Regulation of Electricity Flows _ - Ma vi ma I ram ilatnrv hsmkim fnr 9011 íf!7orh Roni ihlir* MW1 o Maximal regulatory backup for 2011 (Czech Republic, MW) > RZV RZ15 RZ30+ RZ30- RZPR RZSR QS10 RZTR+, RZN30+ RZTR-, RZN30- Night Day Night Day Night Day Night Day Night Day Work days 88 88 290 340 500 600 220 360 220 310 Weekends 88 88 290 340 500 600 210 360 220 310 Source: ČEPS, a.s. (2010): Roční příprava provozu na rok 2011, Praha, ČEPS, a.s., on-line text (http://www.ceps.cz/doc/soubory/20101203/RPP_2011 .pdf), s. 4.P3-4.P4. Úprava T. Vlček. Regulation of Electricity Flows Overvoltage Consumption 5:00 6:00 7:00 8:00 Known consumption Base 3800 MW Peak 4500 MW 6:30 Cons. 4300 MW 6:31+1800 MW VTE from neighbour, rising frequency, overvoltage imminent Solution: PHP drop by 200 MW Seconds -300 MW (GSC) Export -200 MW 15 minutes -800 MW (CP, -30 %, maximum without stopping the plant) 30 minutes -100 MW(NP, 10%) With the electricity price of 30 euro the regulation cost 42 000 euro. (200 MW export, 200 MW PHP used, 1400 MW regulated) Export -200 MW 600 MW OMW 900/1000 4400 4200 4000 3800 Consumption ^ 200/400 MWPHP Consumption 4250 MW 0/400 MW 50/400 WP 5^0/2400 WCP 0/300 MW GSC 0 MW Known consumption Base 3800 MW Peak 4500 MW 9:15 Cons. 4250 MW 9:30 Cons. 4200 MW 9:31 Drop in the wind production reported. From 1600 to 0 MW in 30 minutes. Drop in frequency, electricity quality, undervoltage. 10:00 Anticipated cons. 4100 MW OMWWP 200/400 MWPHP Consumption 4100 MW 150/400 M WP 00/396- MWGSC OMW 1000/1000 "MW NP 400/^00 MWWPS 50/2400 MWCP At 10:00 the cons. 4100 MW and import 0 MW. Solution: Seconds + 300 MW RZV (GSC) + 100 MW RZV (WPS partly) 15 minutes + 200 MW import + 300 MWfrest of WPS) + 200 MW (some of the CP) + 100 MW (NP full operation) 30 minutes + 140 MW (rest of CP) With the electricity price of 30 euro the regulation cost 34 200 euro. (200 MW import, 1140 MW regulated) + 200 MW