Features of energy resources

Renewable energy resources

Naturally re-form relatively quickly, so using them does not necessarily reduce future availability

Examples of renewable energy resources

Solar, wind, wave, tidal, geothermal, biofuels

Non-renewable energy resources

Either not being formed, or re-form so slowly that current use reduces the amount available for future use

Examples of non-renewable energy resources

All fossil fuels, uranium

Depletable energy resources

Use can reduce future availability, including all non-renewable resources but also those renewable resources where unsustainable exploitation may reduce availability

Examples of depletable energy resources

Fossil fuels, wood

Abundance

A measure of the amount of a resource that exists, whether it is economically or technologically exploitable or not

Locational constraints

Energy sources that must be extracted, like fossil fuels, must be located in favourable deposits, and those that harness natural processes may depend on regional or local factors, like climate and topography.

Intermittency

The extent to which the availability of an energy resource varies over time

Examples of intermittent energy resources

Wind, solar, tidal energy

Importance of intermittency of an energy resource

If an energy resource is not available at times it is needed, it is difficult to rely on

Predictability

A measure of how well we can predict how much energy will be available from that resource at a given time

Importance of predictability of an energy resource

We can make plans to use alternative resources when the other resource is unavailable

Energy density

A measure of the amount of energy in a given mass of energy resource, or harnessed by a given mass of equipment

Why are high energy density energy resources generally more useful than low energy density energy resources?

• Easier storage and transport

• Easier to reach high temperatures (industrial uses, vehicles)

How can low energy density resources be converted into high energy density resources?

Solar and wind power can be used to electrolyse water to produce hydrogen

Energy density of energy resources from highest to lowest

• Nuclear fusion

• Nuclear fission

• Hydrogen

• Fossil fuels

• Wood

• Wind power

• Solar power

What is the energy density and fuel type of hydrogen?

High energy density secondary fuel

Resource availability

The amount of energy that is available

Importance of resource availability as a factor

There may be abundant resources but these may not be exploitable with current technology or technology that is likely to be developed

Need for energy conversions to increase usefulness

The form in which energy is harnessed is not necessarily the form in which it will be delivered to the end-user

Which forms of energy is the chemical energy of fossil fuels converted between before it is used to power electrical appliances?

Heat, potential, kinetic, electrical

Importance of need for energy conversions as a factor

Some resources that currently seem to be of little use may become important if appropriate technologies are developed to convert them to more useful energy forms

Applicability to specific uses

It can be difficult for society to change to using energy resources with different characteristics

Importance of applicability to specific uses as a factor

Renewable energy resources have different characteristics from fossil fuels and nuclear power - none can reach the temperature levels that fossil fuels create or produce liquid fuels in sufficient quantities to power all our vehicles

Ease of storage

The ease with which we can store energy resources, affected by the form of energy and energy density

Importance of ease of storage as a factor

Energy demand and supply levels vary and rarely balance, so we need to be able to store energy so that it is available when required

Ease of transportation

The ease with which we can transport energy resources from where they are exploited to where they are needed

Importance of ease of transportation as a factor

Energy resources are rarely found in the areas where demand is highest

Environmental impacts

The extent to which an energy resource damages the environment, e.g. pollution during extraction and combustion, or manufacturing of equipment needed for exploitation

Importance of environmental impact as a factor

• Climate change

• Conservation of biodiversity

• Ecologically sensitive areas

• Human health

What is the problem with the environmental impact of an energy resource being considered as a factor in their use?

Some environmental impacts are over-emphasised, e.g. the visual impact of solar farms or wind farms can make them unpopular, however, they have no significant impact on the ability of the planet to sustain life

Technological development

All technologies have a period of development before they can be used practically, after which there is a period of further development when the technology is refined to make it more efficient, effective, and cheaper

Importance of level of technological development as a factor

Can be difficult for new technologies to be financially viable during early development as they have to compete with existing technologies, whose costs of development have already been paid for and have the economic benefits of mass production

Political influences

Governments might provide assistance to particular sections of the energy industry

Reasons the government assists certain sections of the energy industry

• Support development costs of new technologies

• Increase national energy security

• Reduce environmental impacts

Ways the government supports sections of the energy industry

• Financial grants

• Guaranteed price or market for energy produced

• Financial support or compensation for affected communities

Economic influences

• Hidden costs e.g. environmental damage and damage mitigation

• Set-up costs vs running costs

Impact of hidden costs on resource viability

Non-renewable resources like fossil fuels often have negative environmental impacts like acid rain and global climate change, which we don’t understand the full extent of and are not factored into the cost of energy, economically disadvantaging renewable resources

Impacts of set-up costs often being higher for renewable resources

Interest has to be paid on loans for set-up costs, giving renewable resources a disadvantage, reducing financial viability