Distributed Generation

Society has become all but reliant upon electrical energy in order to provide citizens with a host of vital services. From heating and cooling to communications and food storage, the world would quickly enter into a new "dark age" if this type of on-demand energy suddenly failed. However, other concerns such as efficiency and the ability to adopt environmentally friendly methods are just as important. This is why an approach known as distributed generation has become extremely popular.

What is distributed generation in regard to electrical energy systems? How is this type of power generation planned and implemented? What are the specific benefits of distributed generation and are there possible disadvantages? Are there any cutting-edge technologies that are set to further transform this sector? These are a handful of the questions that this article will tackle.

What Exactly is Distributed Generation?

The United States Environmental Protection Agency (EPA) defined distributed generation as an approach to producing electricity that relies upon several methods as opposed to a single technique. The main intention is to provide a reliable source of power while minimising the impact of these systems upon the environment.^[1]

While traditional techniques such as the use of coal-burning plants to produce electricity are still utilised, distributed generation has become increasingly reliant on alternative sources of power. The main intention here is to reduce the use of fossil fuels while still being capable of providing customers with energy on demand. It is thought that "green" technologies will feature even more prominently within the distributed generation sector in the coming years.^[2]

What Types of Resources Can Distributed Generation Systems Employ?

One of the core strengths associated with distributed generation involves the numerous potential resources which can be used to produce power. So, what options are available? The answer to this question is partially based on whether we are referring to the residential or commercial sector. Here are some of the ways that clean electricity can be produced when dealing with a residential market:^[1]

Small wind turbines
Solar power
Gasoline- or diesel-powered emergency backup generators
Fuel cells

In the event that a company (or conglomerate of companies) employs distributed generation systems for commercial consumption, the types of electricity options often tend to increase:^[3]

Solar and wind power
Hydropower
Biomass energy sources
The incineration of solid waste
Biomass or fuel cells

Note here that these distributed generation methods may or may not be used in synergy with other techniques such as fossil fuels or even nuclear power.

How Does a Typical Distributed Generation System Work?

The fundamental principles behind a distributed generation system are not altogether different when compared to those which rely upon a single source of power. The first step involves producing the power itself via one or more of the techniques outlined in the previous section. Whether referring to solar energy or the use of biomass fuels, the electricity plant will feed this power into an electricity grid (commonly referred to as a "grid").

It is also interesting to note that a distributed energy system (DES) will often work in conjunction with more traditional methods. For instance, one common approach involves proactively monitoring peak demand times. These are some of the instances when a traditional power grid may have difficulty keeping up with primary energy consumption requirements. In such cases, distributed generation systems will provide an alternative source of on-demand power.^[4]

How is the Consumption of Energy Monitored and Interpreted Within a Distributed Generation Network?

The ability to provide electric power has taken on a decidedly "intelligent" approach in terms of distributed generation. After all, it is extremely important to gauge ongoing energy consumption in order to appreciate how commercial or residential systems are functioning as a whole. In the past, this was primarily accomplished through the use of standard electric meters that would employ the kilowatt hour as a means to monitor consumption levels. However, the presence of smart meters is now becoming commonplace when used in synergy with distributed generation. This approach offers several advantages including:^[5]

All information is directly relayed back to the power provider.
Outages can be detected much quicker.
Customers have a greater degree of control over their bills.
Some meters even offer smartphone connectivity.

It is also thought that smart technology will help to promote green power, as more efficient energy consumption may reduce the need to construct additional distributed generation plants.

Distributed Generation: All About Planning

Planning any type of distributed generation grid is arguably one of the most important phases, as it will ultimately determine the types of systems that need to be implemented. The first step involves analysing peak load times in order to better appreciate when additional power may be required. This is then measured against the capacity of existing electrical substations. The ratio itself is referred to as a "load profile".^[6]

Once this data has been interpreted, it is next important to research what types of distributed generation options are available. Many variables will be taken into account including the location, access to renewable resources and the overall cost of implementation. For example, areas with few geographic obstacles could employ wind generation while those found close to a major river might instead leverage electricity generation through a series of hydroelectric turbines.

It should be noted that this is a rather basic description of how the distributed generation of power is analysed. There may be other factors to address such as project feasibility, long-term costs and public opposition to the location of the installations themselves.

The Advantages and Disadvantages of Distributed Generation

It is still important to adopt a more objective approach to appreciate the pros and cons of distributed generation. Here are some of the primary advantages:^[7]

Distributed generation systems are more reliable than centralised networks in the event of a fault.
As power generation plants tend to be closer to the consumer, they are more efficient.
Distributed generation principles can be applied within the home.
They represent environmentally friendly alternatives.

Still, a handful of drawbacks must be noted:^[8]

Land use concerns may arise from time to time.
The initial cost of distributed generation systems can be quite high.
Some of these systems still rely upon fossil fuels as a source of power.

Conclusion

What is the future of distributed generation? One major advancement in regard to the future of distributed generation comes in the form of the rather humble fuel cell. The typical hydrogen fuel cell offers a clean source of on-demand power; particularly in the event of a system fault or a partial grid failure.^[9] Direct methanol fuel cells (DMFC) technology is yet another option. In this case, primary benefits include low storage costs, safer refuelling techniques and the sheer abundance of methanol itself.^[10] It is now clear to see what distributed generation has generated such interest in recent times. As the technologies associated with these techniques continue to make advancements, consumers should be able to leverage the benefits associated with such clean and reliable sources of power.