IEEE Power & Energy Magazine - January/February 2017 - 63

CO2 Policy

The 20% GHG reduction target with respect to 1990 is recalibrated as a 14% reduction compared to 2005 (because of
more complete and reliable numbers) and is then subdivided
in two distinct categories (see Figure 2). The primary CO2
policy instrument is the EU emission trading scheme (ETS),
which represents roughly half of CO2 emissions. It affects
energy-intensive industries and the electric power and heat
sector with an emissions cap that decreases by 1.74 percentjanuary/february 2017

12,000
10,000
Net Demand (MW)

one-third of total European generation (in terms of electric
end energy) by 2020. The implications will be different for
different countries, depending on their individual required
targets and actual potential. But a simple calculation for "average" countries in Europe for the period 2008-2020 leads
to the following orders of magnitude observations, which
may seem obvious but do not appear to be fully recognized
by many policy makers.
✔✔ With respect to hydro power (except, perhaps, for some
Eastern European countries), only small increases are
possible, largely due to environmental constraints.
✔✔ As to biomass, the potential is difficult to predict because it competes with other types of land use and there
are competing applications for biomass, such as transportation. In addition, its very environmental sustainability is questioned. Consequently, there is considerable resistance to its use for electricity generation.
✔✔ Wind, both onshore and offshore, is characterized
by an "average" effective number of operating hours
(ENOH) of about 2,200 h/a and about 4,000 h/a, respectively.
✔✔ Solar photovoltaics (PVs) has an "average" ENOH of
about 1,200 h/a.
✔✔ All this leads to capacity factors (CFs) for intermittent
sources (wind plus PVs) as follows:
* onshore and offshore wind/CFs: ~ 25-45%
* solar PVs/CFs: ~ 13-14%.
✔✔ To produce, say, 20 percentage points of the 34% electric end energy with technologies that operate only
13-14% and/or 25-40% of the time requires a large
volume of installed power-generation capacity.
✔✔ If a good deal of wind and sun is available and demand
is low (e.g., during weekends), situations in which too
much electricity is produced will start to arise.
✔✔ However, sometimes (as in the case of a cold spell,
such as the European winter of February 2012) with
temperature inversion, little wind, and dark skies
(hence, no PVs), at 17:00-18:00 h when peak demand
arises in northwestern Europe, very little RES electricity will be produced, requiring classic thermal
backup (as long as electric storage is not available in
bulk quantities at affordable cost).
An example of what a residual load profile could look
like for different levels of wind and solar PVs is presented
in Figure 1.

8,000
6,000
4,000
2,000
0

80 100 120 140 160
Time (h)

0% Wind + Solar PV
10% Wind + Solar PV

20% Wind + Solar PV
40% Wind + Solar PV

figure 1. Net electrical power load during one week for various fractions of annual renewable electrical energy generation.
[Figure based on extrapolated data from Belgian Transmission
System Operator Elia (2016), http://www.elia.be/.]

age points annually up to 2020. The remaining non-ETS sectors (amounting to the other 50% of CO2 emissions) mainly
comprise transportation, the residential and service sector,
small-and-medium-size industries, and agriculture. They
work under a country allocation scheme that should lead to a
10% reduction compared to 2005. As for renewable energy,
the European target for the non-ETS sectors has been split
into individual member state targets (ranging from +20% to
−20%), largely based on GDP per capita. It is important to
understand that both reduction categories are independent of
each other: for ETS, there is a cap-and-trade scheme among
companies in the designated sectors (a market-based mechanism), while for the so-called "reduction sharing effort" in
the non-ETS sectors, the countries are responsible (in the
sectors mentioned).

Target:
-20% Compared to 1990
-14% Compared to 2005
EU ETS
-21% Compared
to 2005

Non-ETS Sectors
-10% Compared to 2005

27 Member State Targets, Stretching from -20% to +20%

figure 2. EU GHG reduction targets following two separate
philosophies, via companies (ETS) and by countries (nonETS). (Source: Memo/08/34, "Questions and answers on the
Commission's proposal for effort sharing," Brussels 2008.)
ieee power & energy magazine

http://www.elia.be/

Table of Contents for the Digital Edition of IEEE Power & Energy Magazine - January/February 2017