Advantages of Hydroelectric Energy

1. Renewable

Hydroelectric energy is renewable. This means that we cannot use up. However, there’s only a limited number of suitable reservoirs where hydroelectric power plants can be built and even less places where such projects are profitable.

2. Green

Generating electricity with hydro energy is not polluting itself. The only pollution occurs during the construction of these massive power plants.

3. Reliable

Hydroelectricity is very reliable energy. There are very little fluctuations in terms of the electric power that is being by the plants, unless a different output is desired. Countries that have large resources of hydropower use hydroelectricity as a base load energy source. As long as there is water in the magazines electricity can be generated.

4. Flexible

As previously mentioned, adjusting water flow and output of electricity is easy. At times where power consumption is low, water flow is reduced and the magazine levels are being conserved for times when the power consumption is high.

5. Safe

Compared to among others fossil fuels and nuclear energy, hydroelectricity is much safer. There is no fuel involved (other than water that is).

Disadvantages of Hydroelectric Energy

1. Environmental Consequences

The environmental consequences of hydropower are related to interventions in nature due to damming of water, changed water flow and the construction of roads and power lines.

Hydroelectric power plants may affect fish is a complex interaction between numerous physical and biological factors. More user interests related to exploitation of fish species, which helps that this is a field that many have strong opinions on.

Fish habitats are shaped by physical factors such as water level, water velocity and shelter opportunities and access to food. Draining would be completely devastating to the fish. Beyond this, the amount of water may have different effects on the fish in a river, depending on the type and stage of the lifecycle. Not all unregulated river systems are optimal in terms of fish production, because of large fluctuations in flow.

2. Expensive

Building power plants in general is expensive. Hydroelectric power plants are not an exception to this. On the other hand, these plants do not require a lot of workers and maintenance costs are usually low.

3. Droughts

Electricity generation and energy prices are directly related to how much water is available. A drought could potentially affect this.

4. Limited Reservoirs

We have already started using up suitable reservoirs for hydroelectric power plants. There are currently about 30 major power plants that are expected to generate more than 2.000 MW under construction. Only one of these projects was started in the last two years.

Advantages of Wave Energy

1. Green

Harnessing wave energy comes without the emission of harmful green house gases. This is the main motivation factor behind further development of this way of power generation. We need to find energy sources that will replace polluting ones (e.g. fossil fuels).

2. Renewable

Like with most green energy sources, wave power is also renewable. Since this energy source ultimately comes from the heat energy that is emitted from the sun, it will not disappear for some time – in fact, several billion years or as long time it takes for the sun to burn out.

3. Enormous Energy Potential

The amount power in that comes in waves is huge. The energy density is typically around 30-40 kW for every meter (2.2 feet) of wave along the shore. As we go further into the ocean 100kW for every meter is not uncommon.

4. Reliable

Waves are hardly interrupted and almost always in motion. This makes generating electricity from wave energy a reasonable reliable energy source (at least when you compare them to solar and wind).

It should be mentioned that the amount of energy that is being transported through waves does vary every year and from season to season. On the northern hemisphere, the average value of November and May could be different with a factor of two or more.

Wave and wind energy has a larger potential during the winter which is a nice synergistically effect with solar energy where the largest potential is in the summer.

5. Area Efficient

A wave farm that is occupying less than a half square mile of an ocean would generate more than 30 MW of power – the equivalent of 20.000 British homes.

6. Offshore Wave Power

Ocean wave energy plants can be put offshore, solving several of the issues that come with power plants closer to the land. The first benefit of offshore wave power is that there is a larger energy potential in these waves.

The larger flexibility as to where to put these offshore wave farms could potentially minimize the negative environmental effects wave power has on the environment.

Offshore wave farms are on the other hand more expensive.

Disadvantages of Wave Energy

1. Environmental Effects

Power farms on shore that are visible from land may cause conflicts with tourism and local acceptance. Due to this, coastal installations and facilities on land has to meet higher restrictions in terms of size and location.

We don’t yet know exactly how wave power affects sea life. We will hopefully in the next following years have more data in this area.

2. Costs

Wave power is in very early stages of development, which makes speculating on costs harder. Wave resources, connections to the power grid and the lifespan of the technology are just a few factors that result in different costs for different projects. Of these factors, the lifespan is the most uncertain one, since this is a relatively new technology and we are lacking data on how long these wave power inventions realistically can operate.

At the moment, the costs of wave power are generally very high. These power plants cannot be developed without sufficient funding from the governments. On the other hand, renewable energy is the future, and the costs are expected to drop when larger facilities are up and running.

Many of the parts that are involved in wave power generation require regular maintenance. The fact that some of these parts are under the water does not make it any easier – or cheaper for that matter.