With businesses under increasing pressure to reduce greenhouse gas emissions and with regulatory oversight tightening, investing in renewable energy has never been more important.
However, renewable energy is a notoriously broad and complex topic. This article will ask “what is renewable energy?” focusing on the different types of renewable energy available, and how each can be utilised to reduce GHG emissions and ensure regulatory compliance.
At CFP Energy, we stand at the forefront of the energy transition. From power purchase agreements (PPAs) to renewable energy certificates (RECs), we can assist you on every stage of your decarbonisation journey.
Contact our energy team today to access renewable energy.
By utilising the sun’s ability to excite electrons on the surface of photovoltaic cells, solar panels convert sunlight into electricity. The benefits of this type of technology are twofold: because sunlight is constant throughout daylight hours, it doesn’t have to be conserved like non-renewable sources of energy. Also, because solar panels have no moving parts, they are easy to manufacture and set up.
In practice, there are a number of different ways to implement solar panels.
The most common solar panel setup is where they are directly mounted onto the rooftop of a building. This approach maximises unused space, while providing immediate energy generation at the point of consumption. The types of buildings that lend themselves well to this type of design include office buildings, schools, warehouses and distribution centres.
For companies where roof space is limited or under-prioritised, ground-mounted arrays present another solution. More accessible than rooftop designs, this type of array has the advantage of being relatively easy to repair and maintain. Because this design is most effective in open areas, they are especially suitable for businesses set within large plots of land, such as data centres or manufacturing plants.
In contrast to mounted or building applied photovoltaics (BAPV), a BIPV installation is when the photovoltaic collectors form an integral part of the building. Solar systems of this type typically replace exterior shell components, such as windowpanes, or can be integrated into them. Examples of BIPVs include windows, skylights, awnings, canopies, shingles and exterior wall panels.
Wind turbines work by harnessing the kinetic energy of wind. Driving turbines connected to generators, they convert mechanical motion into electricity.
In general, larger offshore turbines capture more energy than their onshore equivalents. This is because wind speeds are generally higher at sea than onshore. This also applies to coastal areas, where wind speeds tend to be much higher than those recorded further inland.
However, onshore wind power can be effective within certain industries. Organisations like manufacturing plants and data centres, for instance, typically use on-site wind turbines to reduce their reliance on the electricity grid, or to help meet targets outlined in the UK ETS and EU ETS, where greenhouse gas emissions must be reduced or offset with allowances.
Wind power also complements other renewable energy sources. For instance, because wind speeds generally peak during evening hours, and solar energy is generally highest around midday, combining the two can increase the consistency and reliability of power output.
Hydroelectric systems generate electricity by channelling water through turbines connected to generators. In large-scale systems, such as dams, the kinetic energy generated by the flow of water can create up to 22,500 MW in peak output.
Another type of hydropower, called pumped storage hydropower, works like a giant battery. A PSH facility can store the electricity generated by other power sources, like solar, wind, and nuclear, for later use. These facilities store energy by pumping water from a reservoir at a lower elevation to one at a higher level.
During periods of high electrical demand, the water stored in the upper elevation is released back to the lower reservoir and turns a turbine that generates electricity.
Hydropower’s main advantage is its longevity. While wind turbines need to be regularly upgraded, hydro plants can typically operate for 75 to 100 years without any significant upgrades.
Geothermal energy is heat that is generated within the Earth, harnessed by geothermal power plants that utilise this natural form of energy as a clean energy source. The two main types of geothermal energy are shallow geothermal energy and deep geothermal energy.
Shallow geothermal energy is used in ground source heat pumps (GSHPs). These extract underground heat through closed-loop or open-loop systems for use in nearby buildings. The benefit of this type of geothermal is that it utilises ‘low grade’ (<500m depth) energy that can be drawn and used at source, making it an ideal energy-efficient alternative to boilers.
Deep geothermal, by contrast, extracts energy at much greater depths (>500m) and can be used in electricity generation as well as heat production. Because this type of energy is continuous, geothermal power plants can operate at their maximum capacity throughout the day and year.
The one downside of deep geothermal is its extreme location inside the Earth. Exploitation of deep geothermal systems requires the drilling of deep wells to reach temperatures that are high enough for direct use (without a heat pump) in district heat networks for domestic or commercial space heating, industrial processes, or agriculture and power generation.
In the context of energy, biomass refers to any organic matter that can be used as a fuel. Examples of biomass include forest residue, food waste, and specially grown energy crops. When biomass is harnessed as an energy source, whether in the form of biogas or biofuels, the carbon released can be captured by other biomass, helping to support a closed carbon cycle.
In practice, biomass can be converted into energy sources through many processes, including:
Direct combustion is generally considered a low-efficiency and high-emission method of biomass energy conversion, utilising as little as 20-30% of biomass’s potential energy. Derivatives of biomass, such as liquid or gaseous fuels, by contrast, use a much higher percentage of biomass’s energy.
This makes biomass particularly useful as an energy-efficient alternative to conventional diesel fuels. Biodiesels, such as HVO, for instance, can reduce greenhouse gas emissions by up to 85%, depending on the type of biomass used, while other biodiesels, like FAME, claim greenhouse gas reductions of up to 90%.
As mechanisms like carbon pricing continue to affect transport sectors like aviation and shipping, biofuels will become increasingly prevalent as a proven way to abate emissions and decarbonise operations.
Tidal energy is a type of renewable that utilises the kinetic energy released by the rise and fall of tides. Tidal currents with sufficient kinetic energy occur when water passes through a constriction, causing the water to move faster. Using underwater turbines to capture this flow, tidal energy can be converted into renewable energy to power lights and heat homes.
Similar to wind turbines, tidal turbines have blades that turn a large rotor. Installed at sea within narrow channels or straits that allow a high velocity of current, the mechanical energy produced by tidal currents turns turbine blades, which in turn power a generator that outputs electricity.
Tidal barrages use infrastructure similar to a dam called a barrage. The barrage is installed across a natural inlet, such as a bay or lagoon, that forms a tidal basin. Sluice gates on the barrage then control water levels and flow rates to allow the tidal basin to fill on the incoming high tides and empty via a turbine on the outgoing tide.
Unlike submerged turbines that are independently positioned, tidal fences feature turbines mounted on the seabed in a continuous fence-like structure. Tidal fences harness the energy of tidal currents and tidal streams (through incoming and outgoing tides) to generate renewable electricity.
All of these forms of tidal energy help support other types of renewable energy, ensuring that the UK’s electricity grid supports a broad range of energy sources to achieve continuous and consistent power.
While each of the energy types covered in this article provides a significant edge over fossil fuels, each energy source has its limitations.
Cloudy or overcast days can reduce solar power output, while low winds can bring wind generation to a halt, much as intermittent droughts or dry spells can reduce hydropower production. So that national grids supply a clean and continuous source of power, a balance of renewable energy types is required, ensuring energy resilience well into the future.
At CFP Energy, we provide a range of renewable energy products to add to your energy mix.
From power purchase agreements (PPAs) to renewable energy certificates and renewable Energy Guarantees of Origin (REGOs), we can help your business access clean energy, reduce emissions, and help you meet your carbon emission obligations within the UK ETS and EU ETS.
Get in touch with our team today to see how we can structure your access to renewables.