Pros and Cons of Hydroelectric Power - Renewity

Pros and Cons of Hydroelectric Power

Green Coast is supported by it’s readers. We may earn an affiliate commission at no extra cost to you if you buy through a link on this page. Learn more.

Hydroelectric power has been a great resource of energy for years. What are the true pros and cons of hydroelectric power?

Pros and Cons of Hydroelectric Power

Hydroelectric dams are a great resource for electric power. There are some drawbacks to hydroelectric power as an intermittent energy resource.

Green Coast can be a resource to help you understand the pros of hydroelectric power as well as the cons of hydroelectric power.

What is hydroelectric power?

Hydroelectric power facilities are a form of power-producing plants that rely on the use of dams to produce consumable energy. Hydroelectric power has a long-standing history as being one of the most reliable and understandable forms of generation.

Usually, hydroelectric power plants are placed in line with dams. The theory is that dams hold significant pressure of water behind them from a reservoir or river. The water can be released into a penstock that will use gravity to flow through a turbine that will generate the consumable power.

It’s interesting because hydroelectric power plants and coal power plants produce electricity in a similar fashion.

Both hydroelectric power plants and coal power plants use a propeller-based turbine to generate power. With coal-based power plants, they use steam from the coal to turn the blades whereas hydroelectric facilities use water.

This is why hydroelectric dams are one of the purest forms of renewable energy. They simply use water (already river flowing water) to generate power. Hydroelectric power does not rely on a consumable feedstock to run the facility like biomass.

Hydroelectric Power Technologies

There are a number of different hydroelectric power technologies some of which are more proven than others. Here is a brief overview of some of the other hydroelectric power technologies.

1. Conventional Hydroelectric Dams

Conventional hydroelectric power dams are the most known technology. The power is built up from pressure from the dam. Then, the water flows down a penstock to the turbine to generate electricity.

2. Pumped Storage

The demand is not consistent with electricity.

<h2><strong>What is Peak Demand?</strong></h2> In most of the cases, utilities measure the average demand for electricity over 15 minutes. In order to so, a utility company adds up the consumed energy and then divides it by the time interval. This offers the total units of power consumed in kW.<br />The peak demand is the highest average energy consumed. This is the peak electricity demand, which relates to the energy consumed during the respective month. A large portion of your energy bill represents the peak demand. It depends on the rate structure of a particular utility.<br />Another peak demand definition suggests that it is the highest usage of electricity in a given time frame. Utilities and generators measure peak demand in kilowatts (kW).<br />Usually, <a href="https://greencoast.org/kw-vs-kwh/">kilowatt-hour (kWh)</a> is the unit, which the utilities use to measure total consumption.<br />The given period of time used for calculating the total consumption may sprawl over a monthly or quarterly basis. <div align="center"><iframe src="https://www.youtube.com/embed/DiPLN77VO7g" width="560" height="315" frameborder="0" allowfullscreen="allowfullscreen"></iframe></div>   <h3><strong>Breaking Down the Peak Demand Definition</strong></h3> In order to know what does peak demand means, you have to understand the mechanism of energy production and its consumption. Peak demand relates to the surge in power usage for a specific time frame.<br />With a view to present the peak demand example, consider the time of the day when most of the users consume the major portion of electricity. When people get up in the morning, they switch on the lights, microwave, coffee maker and similar other appliances.<br />During the day, most businesses and households utilize an excessive amount of electricity. The time when energy consumption reaches its peak is the peak demand scenario. At that particular time, your utility must provide the required amount of electricity to avoid power breakdown.<br />Similarly, the power generators must also increase the production of electricity by anticipating the surge in demand. The utilities charge the high cost for electricity provided during the peak demand.<br />An average electricity bill includes 30-70% of the peak demand charges. The increase in peak demand rates depends on a variety of factors.<br />These factors include utility provider, region, pricing structures, and tariffs. Therefore, these charges vary in different parts of the state.<br />The basic reason behind this increase in the cost is to manage the supply by discouraging the consumers to utilize an excessive amount of electricity during this phase.<br />To lower your energy bills, you need to know how to reduce peak demand consumption.<br /><strong>See Related</strong>: <a href="https://greencoast.org/free-electricity-on-weekends/">How to Get Free Electricity on Weekends</a> <h3><strong>Benefits of Peak Demand</strong></h3> By knowing the peak demand, it is possible to bridge the gap between supply and demand. This allows the suppliers or utilities to overcome the issue of power breakdown. Hence, ISOs take into account the factors associated with the peak demand and use it to identify the true capacity.<br />It helps to meet the demand and makes the performance of a grid more reliable. This results in managing wholesale pricing and making energy markets more competitive.<br />ISOs utilizes huge networks of power plants, which are capable of generating the required amount of electricity. It helps to improve the efficiency of suppliers and manage the baseload.<br />With an increase in energy demand, the ISOs bring additional power plants into action. This, in turn, satisfies the demand. Peak demand allows the ISOs to anticipate the energy demand and make it available when needed.<br />The cost of those power plants, which produce electricity during peak demand is much higher than the ordinary facilities. This is so, as these power generators require additional expenses to maintain them during low demand.<br /><strong>See Related</strong>: <a href="https://greencoast.org/best-solar-panels/">Best Solars Panels to Buy</a> <h3><strong>How Peak Demand Works</strong></h3> Peak demand serves as the major factor, which suggests that how many power generators an ISO or utility must engage in. Peak demand is usually at its highest ranking during summer. This may lead to unexpected blackouts due to higher energy consumption and lower supply.<br />Peak demand affects the energy bills extensively. This means that even if two consumers utilize the same amount of electricity, the energy bill may not be the same. The reason for this difference is the utilization of electricity during peak demand.<br />Usually, peak demand instance occurs during the hot summer afternoon. During this time, most of the air conditioning units are running at their full capacity. The energy usage is 5 times higher than the average consumption.<br />Although the building is consuming the same amount of energy during the peak demand instance, the electricity charges are not the same. This leads to an increase in the energy bill, which is one of the most noticeable peak demand problems.<br />Utilities increase the cost of providing electricity during peak demand. These charges may differ depending on the type of tariff you are obtaining.<br />The most common charges, which usually cast the highest impact on the cost of electricity include: <ul> <li>The energy charge (measured in kWh)</li> <li>The demand charge (measured in kW)</li> </ul> If you don't know the difference between kWh and kW. Read our guide on <a href="https://greencoast.org/kw-vs-kwh/">kW vs kWh</a>. Utilities normally charge for the consumption of energy, as it relates to the amount of fuel utilized by a generator to produce electricity. The reason for charging in kilowatts of demand depends on the fact that it relates to the maximum capacity of a utility.<br />The generators need to produce the required amount of electricity during the instance of peak demand. The residential consumers enjoy the exemption from demand charge, as the utility companies tend to pass on savings to these consumers.<br />On the contrary, industrial and commercial utility customers have to pay for the demand charges. This is so, as these consumers exhibit a huge amount of variability when it comes to energy consumption.<br />You can reduce peak demand by opting for <a href="https://greencoast.org/category/energy-storage-blog/">energy storage</a> and dispatch that energy during peak hours of the day.  If you pair <a href="https://greencoast.org/terms/solar-plus-storage/">solar plus storage</a> together, you can live completely off the grid.<br /><strong>See Related</strong>: <a href="https://greencoast.org/direct-energy-review/">Direct Energy Review</a> <h2><strong>Conclusion on Peak Demand Definition</strong></h2> Peak load is the time when the demand for electricity is at its highest level. Generally, the duration of peak demand instances is shorter. However, in order to meet the demand for such a period, the utilities and power generators have to plan their production in advance.<br />The peak demand is the difference between the highest demand and base demand. In order to meet such an increase in electricity demand, the utilities engage additional power plants.<br />The cost of electricity produced by these generators is relatively higher, which also increases the cost of the ultimate consumer's energy bill.<br />The examples of peak load power plants include gas plant, solar power plants, wind turbines, and diesel generators. <h3>Related Terms</h3> <ul> <li><a href="https://greencoast.org/terms/grid-defection/">Grid Defection</a></li> <li><a href="https://greencoast.org/terms/pjm-interconnection/">PJM Interconnection</a></li> <li><a href="https://greencoast.org/terms/ancillary-services/">Ancillary Services</a></li> <li><a href="https://greencoast.org/terms/electricity-spot-market/">Electricity Spot Market</a></li> <li><a href="https://greencoast.org/terms/frequency-regulation/">Frequency Regulation</a></li> </ul> <h3>Related Resources</h3> <ul> <li><a href="https://greencoast.org/electric-meter-reading/">Electric Meter Reading Guide</a></li> <li><a href="https://greencoast.org/quotes-on-climate-change/">Inspirational Quotes about Climate Change</a></li> <li><a href="https://greencoast.org/master-metering/">Master Metering vs Utility Sub-Metering</a></li> </ul>" class="glossaryLink " target="_blank" >Peak demand is often at night time when the sun goes down and people consume power at the comforts of their home. Pumped storage is a form of energy storage that enables the use of water to act as a storage facility and can dispatch electricity in times of need.

Diagram showing daytime with water flowing downhill to produce electricity and nightime, water pumped back to storage pool above turbines, for later use.
Pumped Storage Example (Source: Water USGS)

3. Run-of-the-river

Run-of-the-river facilities rely on a consistent supply of water coming from a lake, pond or reservoir upstream. The water comes from ‘upstairs’ and flows down the stairs in the penstock to run straight through the turbine.

4. Tide Energy / Wave Energy / Tidal Power

Tidal energy solely relies on the rise and fall of the tide in the ocean. Permitting is very tough for this form of hydroelectric power and is not readily available in every location around the globe. You can read more about Tidal Wave energy in our featured post.

What are some interesting facts about general hydroelectric power to help you understand the advantages and disadvantages of this renewable energy technology?

Let’s dive into the pros and cons of hydroelectric power.

Pros of Hydroelectric Power

When evaluating the pros and cons of hydroelectric power, I like to consider the pros side of the equation first. Here are the advantages and interesting facts about hydroelectric power.

1. Long-lasting asset class

Hydroelectric dams can last over 100 years. Hydro energy is extremely reliable and have a long operating history to stand behind.

2. Simple, understandable technology

The best part of hydroelectric power is the limited complexity. It really doesn’t need to be explained in careful detail. The technology can virtually be used around the globe so long as there is water. It is as simple as when the water flows through the penstock, the facility is running.

3. Low-cost installation and low operating cost

The install cost of hydroelectric facilities is very low when paired with a dam. To operate a hydroelectric facility, you do not have much in the way of operating expenses. You will typically have an operations and maintenance contract with a provider to oversee the power plant.

In addition, you will have some consumable power on-site for operating the facility along with property taxes. Beyond that, hydropower has a limited operating expense burden.

4. Flexibility of use

Hydro energy is very flexible to ‘turn on’ and ‘turn off.’ It is a renewable energy resource that can be shut down during low river flows with a limited operating expense, which won’t burden the overall performance of the facilities over a span of months.

Once flows are at peak levels, the hydroelectric power facilities can be ramped up very quickly to take advantage of the peak points. Large-scale hydroelectric facilities are usually front of the meter rather than behind the meter.

This being said, they have extremely high capacity factors. The plants generally are able to operate at their full capacity. Here is a video on what capacity factor means. 

 


 

Cons of Hydroelectric Power

Just like anything in this world, there are always considerations for disadvantages relative to the advantages.

I’ll let you be the judge if the advantages outweigh the disadvantages. Here are the disadvantages of hydroelectric power.

1. Water loss

One consideration that is a very important one with hydroelectric dams is water loss. During the water turbine process, a portion of water is lost from evaporation.

Water is a very scarce resource for people on earth. Water is a renewable resource. Here are a few reasons why water is renewable.

However, we only have a finite amount of supply of good drinking water and any lost water is damaging. We as people of earth must conserve as much water as possible.

2. Land damage and blockage of reservoirs

The permitting process for hydroelectric power facilities is long for a reason… The development of dams typically damages the low-points in reservoirs.

These reservoirs are typically in biologically rich areas or in riverine valleys. After the water flows through the turbine, the sediment can scour the river beds.

3. Risk of large-scale failure

Traditional hydroelectric dams have large pools of water behind them. With natural disasters on the rise and getting worse as time goes on, these catastrophic events can literally demolish a dam completely.

Tidal power also faces a similar risk with typhoons and hurricanes. Run-of-the-river facilities run less risk since the facilities can be geographically located in climates without hurricanes.

Conclusion on Hydroelectric Dams

There are plenty of pros and cons of hydroelectric power. Hydroelectric dams are one of the best forms of renewable energy. Unfortunately, due to the long history of the technology, most of all dams are spoken for in regards to hydroelectric power. Most hydroelectric development has slowed.

This is due to the long permitting processes and most development locations have been already called for. Hopefully, development can be reinvigorated through the exploration of newer technologies like tidal energy.

Existing operating hydroelectric facilities are very attractive for investors due to the flexibility when paired with other asset classes. From a portfolio construction standpoint, they make a lot of sense for yield-based investors since the cash flow from the facilities is straightforward, proven and relatively predictable.

What are your thoughts on the pros and cons of hydroelectric power? Please let us know in the comments below. We’d love to hear from you.

Understand other renewable energy technologies? Check out our renewable energy section for more information about the facts of renewable power.

Related Resources

Reader Interactions

Leave a Reply

Your email address will not be published. Required fields are marked *

Read Next

Get Your Free Guide to Installing or Buying Solar Panels

  • Exact answers to help you install solar and start saving money on electricity.
  • Key questions to ask your salespeople and installers
  • Easy to print guide that you can take on the go!

Privacy Policy: We hate spam and promise to keep your email address safe