IEEE Power & Energy Magazine - January/February 2017 - 17

✔ Latin America is one of the world's most hydro-energy dependent regions. However,

recent prolonged droughts have sparked numerous operational and system planning
issues, thus renewing interest in conventional thermal investments for dispatchable
generation, with demand for both fossil fuel and electric power increasing rapidly
across the region. The gas market continues to grow, owing in part to ample new investment in liquefied natural gas (LNG) infrastructure planned by Chile, Colombia,
and Uruguay.
✔ In Eastern Asia, natural gas tends to be a scarce resource and today is mainly imported through
LNG terminals. Gas-fuelled electricity generation is used, at best, for mid-load generation-
except in Japan, where, after the Fukushima nuclear plant disaster, CCGT plants have operated
as base-load plants. Although coal remains king, the role of gas could expand, given local concerns about air pollution and the increasing availability of pipeline gas from Russia and central
Asia. Technically, China has the world's largest recoverable shale gas resources; however, this
potential is constrained by geological complexity, shortages of water, and land access difficulties, as well as by limited industrial experience-all of which led the country to lower its
production targets. China's gas consumption has been increasing faster than its production over
the past five years. This trend is likely to continue because the 13th Five-Year Plan (2016-2020)
stipulates that coal in nonpower sectors be replaced with either natural gas or electricity.
✔ In Europe, gas power is considered an important technical resource for renewables integration, but it is currently struggling to be economically competitive: several gas power
stations have been mothballed, and utilities are calling for payment mechanisms to keep
plants online. The situation has been aggravated by flat or, in some countries, declining
electricity demand, low coal prices, and weak carbon markets. In parallel, efforts to decarbonize the gas network and reduce import dependence are increasing: biogas production
is growing, although from a small base, and several power-to-gas demonstration projects
have been commissioned.
In all these regions, the inevitable penetration of variable generation and electrification of
heat and transport will lead to increasingly variable operation of thermal dispatchable generators (this is already being observed in Europe).
The growing net-load variability affects not only
power stations but also networks and gas supply
systems (e.g., gas storage and LNG tanks).
In this article, we discuss the gas system's
ability to meet the electricity system's flexibility
requirements and also explore some of the technical, economic, and policy measures required
if gas is to become a flexibility resource. We analyze flexibility in three parts of the system:
✔ from gas power generation-technology and electricity market design
✔ in gas supply-gas storage and gas/electricity market coordination
✔ through multiple-input, multiple-output plants and appliances.

Innovating Gas Systems to
Meet the Electricity System's
Flexibility Requirements

Flexibility from Gas Power Generation:
Technology and Electricity Markets
Impacts of Flexible Operation and Technology Development
From a technical perspective, gas turbine-based plants are typically more flexible than
many other forms of generation, able to start quickly and having significant ramping
capability (Figure 2). In many cases they are an ideal complement to variable renewable energy. For example, Ireland has, simultaneously, a very large penetration of wind
and gas-fired electricity generation. Modern gas turbine plants excel, with startup times
of lower than 1 h and ramp rates above 50 MW/min. Older coal plants, heavy oil, and
nuclear plants often require four to eight hours for start up and have lower ramp rates
(few MW/min).
january/february 2017

IEEE power & energy magazine

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