Integrated modelling review - Modelling Distributed Energy Resources in Energy Service Networks - page 20

and operational issues yet to be solved; what is clear is the unavoidable collaboration
that the power and transport sectors will have to build in order to meet the challenges
PHEVs face [19,74].
The literature review shows current studies lack technical depth because
researchers can only perform simulations with limited data available from auto man-
ufacturers [26] and travel surveys [104]. Hence, there is an imperative need for
transport and power system research groups to join efforts in order to gain reliable
information on vehicle driving profiles. For example valuable data could be gathered
by using global positioning system (GPS) technology to identify vehicle travel pat-
terns [105]. Otherwise, it will be difficult to model temporal and spatial elements
of PHEV loads in networks. For the previous reasons, initial PHEV studies have
focused instead on a system-wide basis, such as how PHEV market integration can
affect centralised power generation and the existing energy-delivery business models
[106-110].
Energy utilities have some concerns with the introduction of PHEV technol-
ogy. For instance, electrification of the transport sector could increase generation
capacity and the infrastructure requirements, especially if these types of vehicles
are charged during periods of high demand [111]. Consequently, stakeholders need
to estimate the net costs associated with this new load type, including possible
benefits or drawbacks of system utilisation through non-optimal controlled PHEV
charging. These relevant concerns have encouraged high-level research focusing on
the techno-economical impacts PHEVs might provoke in regional US electric grids
[112-116].
Reports from regional power grids attempt to obtain answers to the next questions:

What are the system benefits associated with controlled PHEV charging?

●

What are the emission and marginal costs associated with PHEV charging?

●

As a consequence from the above questions, these studies look at data from differ-
ent PHEV penetration rates and charging scenarios and then are added to estimated
utility loads. Outputs from these simulations - illustrated in Figure 2.4 - give an
estimation of the daily load profiles that might develop over time and which utilities
need to be prepared to supply. General results illustrate that if charging occurred
in the early evening then peak loads would be raised and demands would be met
by marginal power generation ( e.g. usually natural gas combined cycle plants in the
USA). Concurrently, night-time charging does not increase generation capacity or
peak demand, although the base system load does rise. Definitely, PHEVs could
reduce greenhouse gas emissions; however, if the type of marginal plant used to
satisfy EV battery charging is carbon intensive then it could offset the emissions'
reduction estimated from PHEVs displacing petrol.
Because of PHEV deployment, utilities should see substantial revenue growth
due to the electrification of the transport sector. This added revenue would come
with the burden of replacing transformers and reinforcing feeders where appropriate;
hence, a thorough PHEV infrastructure layout and reinforcement program is war-
ranted to meet consumer expectation. Likewise, DNOs should be collaborating with
local authorities to meet their goals with the least possible disruption to third parties.