Over the next two decades, utilities and other types of energy providers will be increasingly pressurized by the government, public and the market to meet the challenge of meeting stretch targets in electricity provision. This task is one that affects every aspect of the electricity grid – from massive generators down to the smallest end-user. At the same time, there are a series of issues – structural, political, economic and practical that impact and interact at the top of the energy hierarchy. These are most effectively solved together, rather than separately.
Growing demand for energy
The first and greatest challenge is energy demand. According to the US EIA, global demand for electricity is set to grow from total installed generating capacity of 4,623GW in 2008 to 7,272GW in 2035. This represents an increase of nearly 60% by comparison with current energy requirements.
A significant proportion of this increase is expected to come from developing nations such as India and China, which are engaged in projects that will dramatically increase their generating capacity. In addition, a large portion of the rural population will be connected to the national grid for the first time.
Still, a good deal of this growth will need to come from nations already identified as developed – and while this may represent a far smaller level of increase proportionately, it is nonetheless large in absolute terms.
An increase of 60% would, of itself, be challenging. This is due to the changing profile of energy demand, as well as available energy sources. One factor that is leading to a major change in the sources from which energy is drawn is an exhaustion of certain types of fossil fuel, with obsolete fuel sources such as oil being replaced in the generation mix by newer fossil fuels such as natural gas. In parallel with this natural shift is a change in energy profile brought about by a mix of environmental and political pressures. Global agreement that fossil fuels lead to too much greenhouse gas emission that in turn may be harmful to the human race has been reinforced by concerns over energy security. This leads to increased pressure for renewables to form part, or all, of the future energy mix.
There is a gradual transformation of the electricity generation domain for two reasons:
- The evolution of renewables is neither constant nor equal - some renewable energy sources are competitive in cost terms to traditional fossil fuel sources now. Others are becoming competitive over time, but are still some way off from being able to supply energy at a rate comparable to that for fossil fuels
- The use characteristics of electricity are not uniform, but vary according to fuel - some fuels are most appropriate for supplying baseload electricity. Some are better adapted for the provision of peaking power. Some renewables, especially wind and solar, are highly intermittent in their energy yield and this intermittency must be factored in to the way that they are used
It is not possible simply to switch generation from one fuel type to another, unless they have broadly similar generating characteristics and they perform broadly similar functions within the electricity mix. Nor is it sensible – with the possible exception of nuclear - to move to a single fuel economy, as this risks serious mismatch between energy generation capability and energy use profile.
Decisions about the preferred energy mix and investment in the appropriate plant to handle that mix rare normally made years in advance. Often, knowledge as to the costs of energy within the system and the likely user profile for that energy are not always completely known. Only the course of time and ongoing research will slowly remedy this uncertainty.
Engerati Transmission and Distribution Report