IEEE Electrification Magazine - March 2014 - 87

Centralized
Sending
Signals/
Prices,
Receiving
Preferences/
Bids

Smart Retailer/Service Provider

External Services
Load
Forecasting

Meter Data
Analysis

RES Generation
Forecasting

HEM Signal
Optimization

Smart Grid Product
Development
Energy Feedback
for Customers

Rating and
Billing

Price
Forecasting

Aggregation Level

DSL
PLC, BPLC
GSM
IP

Metering Data
Concentrator

Smart House

Decentralized
Receiving
Signals/
Prices,
Delivering
Preferences/
Bids

HEM
Concentrator

HEM User
Interface
ZigBee
PLC,
Z-Wave
IP

Consumption
Monitor Interface

Concentrator
Home Gateway

Devices and Device
Control

Smart Meter

RES: Renewable Energy Sources
PLC: Power Line Communication
HEM: Home Energy Management
BPLC: Broadband Power Line Communication
GSM: Global System for Mobile Communications
Figure 3. The architecture of loose coupling via services.

energy butler devices from october 2010 to august 2011,
with further ongoing data acquisition and documentation:
xx
the first phase with new energy management/variable tariffs started in october 2010. the customers
received a first variable tariff on a monthly basis
and access to the Mvv metering portal. the customers could shift their loads according to this variable
tariff manually.
xx
the second phase started in december 2010. since the
energy butler was still not available to all customers, a
new tariff model was introduced to get a better statistical basis for the evaluation of the load shift potential.
in parallel, the energy butler was installed and tested,
first at up to ten selected friendly customers followed
by the installation of the other 90 energy butler devices with all peripheral devices (e.g., switchboxes, gateway/modems, and temperature sensors) starting in
spring 2011. this included constant software improvements and installation of the most recent software
updates on the energy butler via remote access.

xx
the third phase started in May 2011 and lasted until

august 2011 when activating the energy butler software allowing the customer to use it not only for
manual but also for automated load shift.

Key Findings and Lessons Learned
Quantitative assessment of the load shift potential requires
comparison between the load curve when variable tariffs
(electricity prices) are applied and the normal reference
case with fixed tariffs. since it is impossible to measure
concurrently the load curve with the two options for any
customer, it was decided to use as the reference case modified standard load profiles considering seasonal effects.
a representative load shift together with the applied, as
obtained for february 2011, is shown in figure 5. there are
several effects that need to be considered with respect to
the load shift. besides the seasonal and price effects,
changes in consumer awareness, saturation, or habitual
effects can be important when tariffs are constant for several months.

IEEE Electrific ation Magazine / MARCH 2 0 1 4

Table of Contents for the Digital Edition of IEEE Electrification Magazine - March 2014