1. Presentation of the case in Japan for Technical Committee K - Integrated Operation of Hydropower Stations and Reservoirs-
Centers for Civil Engineering and Architecture
Kansai Electric Power Co., Inc.
July, 2017

2. Contents Electricity Market in Japan
Case Study in Japan for Optimization of Integrated dispatch of cascade reservoir

3. 1. Electricity Market in Japan- Histroy
History
Electricity market reform in Japan has been started since 2003, and full deregulation of electricity retail business was made in April 2016.
Mar. 2003
Apr. 2004
Apr. 2005
Apr. 2016
Contracted Capacity
(Voltage)
Deregulation
Deregulation
Deregulation
Deregulation
Larger Scale factories
26%
Larger Scale factories and super market
40%
Larger Scale factories
62%
Larger Scale factories
100%
2,000kW
(20,000V)
Regulated
Regulated
50kW
(6,000V)
Small scale/ Household
74 %
Small scale/ Household
60 %
Small scale/ Household
38%
( V)
Japan Electricity power Exchange

4. 1. Electricity Market in Japan- Current Reform Process
Three phases of the current electricity market reform is under the process during
Present
2015
2016
2020
Establishment of the Organization for Nationwide Coordination of Transmissions Operator
Full Liberalization of electricity retails business
Elimination of whole regulation
Legal Structural separation of power transmission/distribution sector
Full liberalization of retail electricity rates

5. 1. Electricity Market in Japan – Overall Scheme
Provision of Back-up Capacity
Original Electricity Utility
Customers
Independent power producers
JEPX
New Electricity Utility
Wholesale Electricity Utility
(J-Power and The Japan Atomic Power Company)
Customers

6. Transaction Volume through Electricity Market in Japan
This graph shows the trend of the transaction volume through Japan Electricity Power Exchange (JEPX)
Only 2.8% (max. 3%) of the total demand of electricity is treated through the market as of Oct
Total demand
Transaction ratio in JEPX
Total demand (Billion kWh)
Transaction ratio in JEPX (%)
Apr, 2012
Oct, 2012
Apr, 2013
Oct, 2013
Apr, 2014
Oct, 2014
Apr, 2015
Oct, 2015
Apr, 2016
Oct, 2016
Source: Ministry of Economic, Trade and Industry, Japan

7. Share of new Electricity Utilities in Japan
Total share of New Electricity Utilities is 7.7% of the total sales.
High Voltage (new Electricity utility)
High Voltage (original Electricity Utility)
Low Voltage (new Electricity utility)
Low Voltage (original Electricity Utility)
High Voltage Share of New Electricity Utility :10.5%
Total Share of New Electricity Utility :7.7%
Total sales (Billion kWh)
Low Voltage Share of New Electricity Utility :2.5%
Apr, 2012
Oct, 2012
Apr, 2013
Oct, 2013
Apr, 2014
Oct, 2014
Apr, 2015
Oct, 2015
Apr, 2016
Source: Ministry of Economic, Trade and Industry, Japan

8. Peak load and interconnection in Japan
There are 10 major original electricity utilities in Japan.
Since 2003, IPP and /or PPSs has been participated in the electricity market.
Source: Ministry of Economic, Trade and Industry, Japan
Peak load and interconnection between different Major Electricity Power Company areas, 2014

9. Sources of Electricity in Japan
LNG
Coal
Nuclear
LNG
Coal
Nuclear
Oil
Pumped storage
Hydro
Oil
Pumped Storage
Hydropower
Renewable
Others
Renewable
Others
Original Electricity Utility
Total of Power Capacity
others
Source: METI, Japan

10. Procurement of Electricity by new Electricity Utilities
Procure from own source or bi-lateral contract
Procure from Back-up capacity
Procure from JEPX
Ratio of back-up capacity
Ratio of JEPX
Full- deregulation
Ratio (%)
Total sales by new Electricity Utilities
(Billion kWh)
Sep, 2012
Mar, 2013
Sep, 2013
Mar, 2014
Sep, 2014
Mar, 2015
Sep, 2015
Mar, 2016
Sep, 2016
Source: Ministry of Economic, Trade and Industry, Japan

11. Incentives for Renewable Energy Producers
Feed in Tariff (FIT) :the Japanese government has introduced a feed in tariff for renewable energy generation since 2012 and found several issues on the current incentives and/or market mechanism such as unbalanced source (90% is solar power) increment and increase burden of customers. New mechanism for renewable energy source is under discussion among the relevant government committees.
Several measures for hydropower development
subsidiary for a study or replacement and/or construction of new hydropower development,
Shortening the approval process/ examination period for small scale hydropower development (less than 2,000kW) such as i) less documentation (avoiding duplication of submittals and unnecessary review of existing water right) , ii) authorization empowerment to provincial level),and iii) others.

12. Optimization of Integrated dispatch of cascade reservoir
Items to be considered
More accurate forecast of rainfall and/ river discharge in each catchment area
long term climate change
short/middle term (daily, weekly, monthly basis)
Optimization of Reservoir Operation
How to decide objective function for optimization of reservoir operation of each dam (flood control, power generation, water supply, irrigation…)
Storage capacity allocation (also allocation of cost/expense and benefit)
Different characteristic of rainfall in each catchment area
Purpose of dam
Hydropower
Flood control
Irrigation
water supply

13. Case Study- share storage capacity for flood control
Tonoyama dam (H=64.5m, Concrete-Arch type ) was completed in 1958, which is owned by Kansai Electric Power Company located in the upstream of Hiki river in Wakayama prefecture, Japan. (P=15,000kW, Q= 26m3/s and He= 69m)
Design flood is 3,000m3/s and effective capacity of the reservoir is 13.8 million m3 for hydropower generation only (originally there is no flood control capacity).
In general, central/ local government is responsible for flood control of each river basin and any private companies have no capacity to control flood unless government shares burden of each dam or makes an agreements in advance.
According to an agreement with the local government, a part of capacity (1.8 Mm3) has been provided for flood control as a cooperation basis since 2012 in case that a large flood is predicted.
Tonoyama Dam
Min. water level
Original
　　112.0m
New target Water level
　　109.0m
Water level to be expected effectiveness of flood control
Capacity for flood control
＋1,857,000m3
Sediment
Capacity for Hydropower generation
Orifice gate
Crest Gate
Dead capacity
Minimum operation water level
3.0m
Location of Tonoyama Dam
Another case study of “Study on validity of the hydroelectric dam operation adopted GSM and the information about typhoons) in the proceedings of ICOLD this year.

14. Summary Hydropower in market (case in Japan)
Incentives for renewable energy has been provided to developers both of original / new power utilities in Japan recently.
Challenges on the current mechanism to expedite development of renewable source in Japan are, i) mechanism for fair/ reasonable tariff determination, and ii) resolve unbalanced renewable energy development.
The optimal operation of reservoirs and hydropower stations.
A case study in Japan is introduced.
Need to discuss contents of TOR-1 further