From consumers to prosumers
Involve the Carros clients with an active energy management through the control of their production-consumption-storage balance
A will of membership
NICE GRID invited Carros consumers, local authority and companies to become “prosumers”. It was a successful collective experiment.
Meetings with Carros’ habitants, with company clusters, were decisive to make them understand the crucial role they would have in the project and in what their participation was a key element of the demonstrator. EDF team achieved this teaching and instructional work.
100% of the large eligible industrial consumers, i.e. 12 industrial clients, will agree to EDF requests. They were already very active in terms of sustainable development, and they will commit to the project without any return. They just wanted to confirm their sustainable involvement.
At the end, 300 residential clients (it represents almost 15% of the eligible Carros households), companies and local authorities will join the project and take part actively into the trials.
Economic benefit as well as the will to take part into a collective effort guided them to manage their consumption expenses, by the financial incentives of the solar hours offer and the desire to act in favor of the environment. The financial benefit and the desire to participate in a collective effort, are the two major reasons that led residential customers to try the summer experiments like those of winter.
Regarding the companies, their motivation consisted in a way to participate to secure the electrical grid in PACA region and to show their wish of being sustainable companies.
A panel of offers
To involve Carros residential consumers in active energy management, 5 offers have been established. Three offers encouraged photovoltaic integration in the summer and the two others encouraged a reduction of peak demand in winter.
Zoom on the three summer offers:
• Solar Bonus offer: During the 40 solar days in summer 2014 and 2015, indicated by alerts sent on the previous day via text and/or e-mail messages, EDF invited its volunteering customers to shift their electricity consumption during solar hours between 12:00 noon and 4:00 PM. At the end of each summer, EDF sent the customer a gift-voucher for a tariff equivalent to the off-peak tariff for their power consumption during solar hours.
• Smart Water Tank: The idea is to store energy with hot water tank. In addition to the solar bonus offer, the hot water tanks were managed remotely in a more optimized way to integrate solar generation. The hot water tank participants automatically switched on during the hours when the panels of the district were the most productive. This recharge proceeded in addition to its usual operation at night, thus preserving customer comfort.
• Smart Solar Equipment offer: This offer includes the installation of solar PV panels installed on the roof and energy storage in a residential battery.
Zoom on the two winter offers:
• Behavioral Load Management: In the winters 2014 and 2015, households who significantly decreased their power consumption between 6:00 and 8:00 PM (during 20 peak demand days) received gift-vouchers in reward for their efforts.
• Electric Heating Control via the Linky smart meter, designed to switch off or cut down the heating system or a short time during peak periods without impacting the participant’s comfort
Two offers were also proposed to the industrial companies by EDF:
• Controlled Load Management offer via remote control of their energy uses (heating, HVAC, domestic hot water, etc.) and/ or processes (steam ovens, refrigeration units, furnaces, etc.), together with remote consumption tracking.
• Behavioral Load Management offer controlled manually following load management requests.
With support from the Nice Côte d’Azur metropolitan authority, smart meters and light dimmers were installed in Carros to reduce power to the public lighting upon load management requests.
86 % of surveyed consumers who had participated to the summer use-cases have been satisfied. They considered their participation interesting, forward looking and with few constraints.
94% of surveyed consumers who had participated to the summer use-cases have been satisfied. They considered their participation useful and easy to adapt.
100% of the companies have accepted to extend the experimentation in 2016.
Solar production in PACA has a strong growth
With a 14% increase in 2015 and with 104 MW of new solar production capacities, the Provence Alpes Côte d’Azur region solar generation capacity has a strong growth. In addition, the strong sunlight increases installations efficiency.
The region goal is to achieve 2300 MW of photovoltaic capacity by 2020.
Integration of photovoltaic production is a major issue for electrical grid
94% of the photovoltaic production is connected to the distributed electrical grid (the low and medium voltage grids). The massive integration of an intermittent electricity production on a grid, which has not been design for those usages, requires it more flexibility in order to avoid constraints.
When households do not consume the surplus of solar production, it is backed up on the grid that involves voltage and power troubles.
Flexibilities, a potential solution
It is need to conciliate the production and the consumption curves to integrate solar production on the grid. “Flexibilities” makes it possible. It is all the actions or capabilities that have an effect on consumers load curves.
In function of consumer’s behaviours, three experimental use cases were proposed. Indeed, high capacity storage devices permit a better integration of photovoltaic production.
Solar hours were a good lever
In France, double electricity tariff exist: on-peak hours (16c€/kWh) and off-peak hours (11.14c€/kWh). Traditionally, off-peak hours are during the night and on peak hours during the day.
During the 40 sunniest summer days, EDF proposed off-peak hours in the day by sending SMS or e-mail to its clients to encourage them consume electricity when the solar production is high.
At the end of the summer, EDF is giving gift vouchers to clients as a value of the money saved by consuming electricity in the middle of the day at off-peak prices.
• Solar Bonus offer
22% of the electrical consumption was moved between 12 noon and 4 PM.
• Smart Water Tank
Difference of 56% on average was recorded in their consumption between a solar day and a “normal” day between the hours of 12:00 noon and 4:00 PM
A major issue for the region
East of PACA region is only producing 10% of its electricity.
Located at the end of the transmission grid, the this territory faces a yearly growth of its peak demand between 6 and 8 PM.
NICE GRID studied the impact of a peak demand reduction at the level of the city (Carros primary substation).
What is the peak demand?
Demand peak corresponds to the highest power demand on the electrical grid. The demand peak reaches its highest level the 8th February 2012 at 7 PM with 102 GW of power demand.
At the PACA region scale, in the winter, the electrical consumption is on average increasing by 245 MW per degree lost.
It is the equivalent of the average demand of a city like Toulon. It is called the grid « thermo sensibility ».
Residential clients were motivated to act
220 volunteer households participated in the experimental trial in Carros during the winters 2014 and 2015.
On peak demand hours, they reduced their power consumption by 21% on average, between 6:00 and 8:00 PM.
77% modified their consumption behaviour in winter 2013/2014, versus 60% in winter 2014/2015.
Companies were very committed
12 companies participated within NICE GRID. Companies located in Carros were highly mobilised: all of the businesses approached with subscribed power above 250 kW (and with demand management potential between 6 and 8 PM).
They all accepted to participate when EDF contacted them. The sum total of business contributions reached 301kW on average, ranging from 184 to 483kW per session, i.e. equivalent to a relative demand reduction of 3% to 9%.
Local authority also involved with public lighting
During pilot testing of public lighting control, the authority of the metropolis Nice Côte d’Azur (NCA) was able to reduce its power consumption to an average value of 18 kW in 8 streets of Carros, equivalent to a reduction of about 30%.
Storage was a solution to reduce peak demand
Four storage systems with a total capacity of 1.3 MW, help to reduce the peak reduction by discharging during on peak hours. An average of 43% of the total power reduction was due to storage systems during 2014/2015 winter.
Islanding in Carros
Within the NICE GRID project, islanding of a district is a sequence:
• Consecutive to the disconnection of the district from the main grid
• During which the district is supplied for a limited duration of time by a storage system and local PV generation
• Involving the maintaining of frequency and voltage by the storage system
• Ending with the resynchronization to the main grid without any interruption of service
Five hours of Islanding in Carros, a successful trial
In October 2015, the district of 1ère Rue have been islanded from the main grid for the first time.
At exactly 11:40 AM, the district has been disconnected from the grid and the storage systems combined with PV production provided the electricity to customers.
Initially charged at 73%, the storage system decreased its charge level to 55% at the end of the experimentations, which could have allowed for four further islanding hours.
Main challenges of this experimentation:
• Disconnection and synchronisation phases were achieved without any interruption of service
• Storage system was alternatively charging and discharging, adapting its schedule in to the solar radiations and electric load
1ere rue district, the chosen place for trials
Located in the Carros’ industrial area, this district was selected for the islanding trials.
Indeed, eight companies consuming up to 100 kW on peak days and three photovoltaic generators representing a total capacity of 430 kWp are located in this area. This district backfeeds almost every day during high generation hours.
Many tests have been conducted before at “Concept Grid”
In June and July 2015, before the installation and the real exploitation of the islanding system in Carros, two test sessions were conducted at “Concept grid”. “Concept Grid” is a distribution grid lab from EDF lab at “les Renardières” (Paris area).
More than 150 tests were conducted there, in conditions close to the real grid of Carros, in order to validate functionalities, performances and robustness of such an islanding system at reduced scale.
Advantages of this islanding solution such as absence of interruption of service, storage flexibility of the battery for supply/demand balance, ability to store the local generation, open various promising applications at the International scale and for the development of micro grids development which upstream supply is weak such as island territories.