PIESA-IERE TIS Africa Lilongwe Workshop Presentation On Trip To IERE-SGEPRI Nanjing Workshop In China By Peter Bobo (Assistant Meter Engineer (Prepayment & Metering Standards in ESCOM, Malawi))
Smart Grid & Energy Efficiency
Smart Grid Efficient Economical Reliable & modernized Environmentally friendly Transparent to stakeholders
Smart Grid Aims 1. Lower total energy consumption 2. So minimize impact of high load on power system (reduce bottle-necks, reduce load shedding) 3. Shift some power usage to off peak times & promotes usage of energy efficient devices & smart devices 4. Advocates integration of renewable energy sources into the grid (decentralized generation & low carbon dioxide emission) Promotes use of electric vehicles
Photograph 1: Electric Bicycles Parked By Hunan Road Near The Westin Nanjing Hotel
Photograph 2: Electric Bicycles Parked In Nanjing, China
Wade Wu, By Hunan Road Near The Westin Nanjing Hotel. (A long line of bicycles behind).
Research Centre (See the Electric bus and the many batteries in the racks)
Smart Grid Re-engineering Problems Intermittent wind or PV power fluctuations Renewables not reactive power sources Customers concern over privacy
Researches to address the problems Generation Transmission Transformation Distribution Consumption Dispatching Information & Communication technology (ICT) Standardisation
VSC-HVDC (Dr Guanfu TANG) (Addressing lack of reactive power in renewables) Use electronic circuit of insulated gate bipolar transistors (IGBT s) Controlled switching compensates for lack of reactive power Also improves fault ride through capability of wind or PV system
Power fluctuations Energy storage used Researching with vanadium redox flow batteries Lithium-ion batteries Lithium-ion super-capacitors Compressed air. Charging & discharging counter power fluctuations
Power fluctuations many geographically diversified sites (Mr. Nagoya of Hokuriku EPCo) Used mathematics to prove that if have many wind farms or PV stations in many areas, there is power fluctuation smoothing effect
Power fluctuations Wind or PV control governor of other generators (Oota Fuji Electric) Wind or PV generator signal governors of far hydro-generators etc of rises & falls of wind or sunlight
In transmission - Superconductivity Around -273⁰c or 0 K Conductor resistance goes to real zero Lots of current flows (even when power source is removed) e.g 100mm² niobium tin can carry 200 000A. 100mm² ordinary all aluminium conductor can carry 301A Very strong magnetism gets created
China s superconducting Transmission Line (Dr Ming QUI of CEPRI) 110kV line Construction at advanced stage Launching next year
Voltage fluctuations - SMES (superconducting magnetic energy storage devices) Super current super magnetism super inductor super oppose current/voltage changes (Lenz s law)
Figure 1: Voltage Transient Response Without & With SMES
VFTO In GIS or HGIS (Mr Wang Lei of SGEPRI) (Very fast transient over-voltage in gas insulated switchgear) Occurs upon switching Gas insulation breaks down damaging switchgear, transformers etc VFTO determining mathematics developed Mathematically derived & live test results not very different Recommends live switching of UHV- GIS is ok
ENERGY EFFICIENCY BY DEMAND SIDE MANAGEMENT
Demand side Management by Energy efficient devices Smart devices Smart EV charging
Privacy Concerns Addressed (Gale Horst of EPRI, USA) Grid to communicate to devices via device control console is proposed Customer sets console according to his priorities
ADDRESSING THE COST EFFECTIVE ISSUE ANOTHER SMART METER PROPOSAL
Proposed meter looks different from Nari Tech made smart meters
RECOMMENDATIONS Seriously consider having technical research institutions Double tariff for dwelling house customers Start off in the smart grid direction
How much saving can we make if instead of using diesel, we use wind or solar power on the islands of our lakes or oceans?
Xie xie (Thank you/ dankie) Ngiyabonga