What is Tidal Energy? Explained

Tidal energy is a renewable power source that harnesses ocean tides through the use of turbines and barrages. Utilizing predictable tidal cycles, it supports clean electricity generation, reduces dependence on fossil fuels, and strengthens sustainable energy systems.

What is tidal energy?

Tidal energy is the conversion of ocean tides into electricity using turbines, barrages, or tidal stream systems, offering a predictable and sustainable renewable resource.

✅ Harnesses predictable tidal cycles for renewable power

✅ Reduces reliance on fossil fuels and lowers emissions

✅ Supports clean, sustainable electricity generation

It is a renewable power harnessed from the rise and fall of the ocean's tides. The ocean's vast power is one of the most promising resources, capable of generating electricity to meet the needs of communities worldwide. With the growing demand for clean, sustainable sources, tide-generated power has been thrust into the spotlight as an effective and environmentally friendly option. Understanding tidal power highlights how Renewable Power Generation technologies are diversifying to create a more sustainable grid.

What is Tidal Energy? It is an ocean energy resource; tide-generated power is extracted from the natural ebb and flow of coastal tides. The key difference between tidal energy and other renewable sources, such as wind and solar power, lies in the predictability and reliability of the high tides. Additionally, the water in the ocean is approximately 800 times denser than air, making it a more concentrated and efficient power source compared to wind turbines. Governments worldwide are encouraging clean projects like tidal power through Renewable Energy Tax Credits, which lower the cost of adoption.

Tidal Barrage Systems for Renewable Power

Two primary methods of capturing tidal energy are tidal barrage and tidal stream generators. A tidal barrage is a large-scale engineering project that involves constructing a dam across a tidal estuary or bay. Then, as the water level changes during the high and low tidal barrage, water flows through turbines, generating electricity. The most notable tidal barrage projects include La Rance in France and the Sihwa Lake tide-generated Power Station in South Korea. 

Tidal Stream Generators and Ocean Turbines

Tidal stream generators, on the other hand, utilize underwater turbines positioned in tidal streams to harness the kinetic energy of the moving water. Like wind turbines, tide-generated turbines rotate as water flows over their blades, converting it into electricity. This technology is less intrusive to the environment and marine life than tidal barrage systems.

Advantages of Tidal Energy for Clean Electricity

There are numerous advantages to utilizing it as a renewable source. First, tidal energy is predictable, making planning for power generation and grid integration easier. Additionally, tide-generated power is environmentally friendly, as it produces no greenhouse gas emissions or air pollution during operation. This makes it a desirable option for reducing dependence on fossil fuels and combating climate change.

Disadvantages and Challenges of Tidal Power

However, it also has its disadvantages. The initial cost of constructing large-scale tidal power plants, particularly large-scale tidal barrage projects, can be substantial. This kind of generation is also limited to specific coastal locations with sufficient range and appropriate topography. Furthermore, concerns exist about the potential impact on marine life and coastal ecosystems, although research is ongoing to develop more sustainable and less disruptive technologies.

Tidal Energy vs Wind and Solar Power

Regarding efficiency, it is competitive with other renewable power sources, such as wind and solar power. In addition, the density of water makes tidal power generation more efficient in terms of power output per unit of installed capacity. However, the technology's scalability and geographic limitations make it challenging to deploy tidal energy globally. Tide-generated systems complement other clean technologies featured in our articles on Biomass Renewable Energy and Clean Renewable Energy.

Environmental Impact of Tidal Power Plants

The environmental impact is generally considered to be low, with minimal greenhouse gas emissions, air pollution, or waste production. However, localized effects on marine ecosystems and sediment transport may occur, depending on the type and scale of the project. Therefore, it is crucial to perform thorough environmental assessments and monitoring to minimize the potential negative effects of tide-generated power installations. To see how tidal power contributes to decarbonization efforts, visit our Renewable Electricity and Renewable Power Sources guides.

Global Examples of Tidal Power Stations

The best locations for generating tidal energy are areas with a high tidal range, strong tidal currents, and suitable coastal topography. Some of the world's most promising sites include the Bay of Fundy in Canada, the Bristol Channel in the United Kingdom, and the northwest coast of Australia. In addition, countries such as France, South Korea, and the UK are already home to some of the largest tide-generated power stations and continue to invest in this renewable power technology. As part of global Renewable Energy Projects, tide-generated power installations provide reliable baseload power alongside solar and wind.

Future of Tidal Energy in Renewable Systems

What is Tidal Energy? Tidal energy is a promising renewable resource with significant potential for generating clean, sustainable electricity. While there are challenges to overcome, such as high initial costs and site-specific limitations, ongoing research and technological advancements aim to make tide-generated electricity a more accessible and environmentally friendly option for the future. For a deeper comparison beyond 'What is Tidal Energy,' explore our article on 'What is Distributed Generation?' which shows how local systems, such as tidal plants, strengthen energy resilience.

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Biomass renewable energy converts organic feedstocks into electricity via gasification, biogas, and CHP systems, integrating with microgrids, power electronics, inverters, and grid-tied generators for reliable, low-carbon baseload and frequency support.

What Is Biomass Renewable Energy?

Energy from organic feedstocks converted to power via gasification, biogas, and CHP, integrated with grid electronics.

✅ High-efficiency CHP improves capacity factor and voltage stability.

✅ Power electronics, inverters, and protection enable grid-tie.

✅ Supports frequency control, reactive power, and microgrid resiliency.

Biomass Renewable Energy is an important source of energy for majority of the world’s population. The use of biomass renewable energy is expected to increase in the near future, with growth in population. In many under developed nations (most especially areas such as parts of Africa, conventional biomass renewable energy dominates national energy strategies, leading to negative impacts on human health and the environment. There are, however, opportunities for developing improved and modern biomass energy technologies, which offer substantial benefits in terms of enhanced quality of energy services and reduction in negative health and environmental impacts. For a concise overview of feedstocks, conversion technologies, and benefits, see this biomass energy overview to understand core concepts.

In addition, the sustainable harvesting of biomass renewable energy resources is essential for ensuring the continued availability of this important energy source particularly for the world’s poor.

Sustainable harvesting practices also align with broader categories of renewable energy sources that emphasize resource regeneration.

Biomass renewable energy plays a vital role in meeting local energy demand in many regions of the developing world. Biomass is a primary source of electrical energy for about two billion people in developing countries. Therefore, it's available to the world’s impoverished nations while providing a suitable energy for cooking and heating. Also, biomass energy-based industries are a chief source of economic development in terms of job creation in rural areas. Modern biomass renewable energy technologies are being widely used in many developing countries as well as in certain parts of the developed world. With proper energy management strategies, supported by appropriate environmental practices, modern biomass renewable energy projects can be a sustainable source of electric power production as well as providing liquid and gaseous fuels. Biomass is therefore not only a central alternative energy source but is probably an important future sustainable energy source. These outcomes contribute to the goals of clean renewable energy that balance access, affordability, and environmental performance.

Growing interest in biomass renewable energy is driven by the following facts among others:

• It can contribute to lessening poverty in developing countries;
• Biomass renewable energy meets power needs without expensive conversion equipment;
• It can deliver biomass renewable energy in all forms that countries need for electricity and heating (in all forms of liquid and gaseous fuels)
• It is carbon dioxide-neutral because as much biomass can be grown as burned
• Biomass renewable energy helps to restore unproductive and degraded lands.

For definitions, policy basics, and key technologies, this guide to renewable energy offers helpful background.

Available statistics indicate that the share of biomass renewable energy in the global energy consumption has remained roughly the same over the last 30 years. Biomass renewable energy accounted for an estimated 14% and 11% of the world’s final energy consumption in 2000 and 2001 respectively (IEA, 1998 and IEA, 2003). The International Energy Agency (IEA) estimates that at global level, the share of biomass in total final energy consumption is comparable to that of electricity (15%) and gas (16%). These figures parallel developments in renewable electricity that are influencing investment and grid planning.

Modern biomass renewable energy technologies have the potential to provide improved energy services based on available biomass resources and agricultural residues19. Widespread use of combined heat and power generation biomass renewable energy options in rural areas can address multiple social, economic and environmental issues that now constrain local development. The availability of low cost biomass power in rural areas could help provide cleaner, more efficient energy services to support local development, promote environmental protection, provide better domestic fuel sources and improve rural life. Bioenergy technologies based on sustainable biomass supply are considered "carbon neutral" and may lead to net carbon dioxide emission reduction if used to replace fossil fuels. For comparative emissions data and lifecycle insights, consult this overview on renewable energy facts to understand trade-offs.

In addition, modern biomass renewable energy technologies can contribute to better bio-waste management. For example, land-fill gas can assist urban waste management, while bagasse-based co-generation reduces the problem of safe disposal of bagasse at sugar plantations. Another advantage of modern biomass renewable energy is its job generation potential – a very important attraction for many developing countries faced with chronic levels of unemployment or under-employment. Existing studies indicate that, in comparison to other primary energy sources, the job generation potential of modern biomass is among the highest. For example, in Brazil, the annual production of 14 billion litres of ethanol from sugarcane is responsible for the creation of 462,000 direct and 1,386,000 indirect jobs in the country, corresponding to a rate of 263,000 annual jobs per MTOE generated. Collectively, these pathways situate biomass within broader renewable alternative energy strategies that enhance resilience and jobs.

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Renewable power generation harnesses solar PV, wind turbines, and hydroelectric resources, using inverters, MPPT, and energy storage for grid integration, power quality, reliability, and decarbonization across smart grids and distributed generation.

What Is Renewable Power Generation?

Electrical generation from wind, solar, and hydro via grid-tied systems, inverters, and storage to cut emissions.

✅ Includes solar PV, wind turbines, and hydroelectric plants

✅ Employs inverters, MPPT, and converters for power quality

✅ Integrates storage, microgrids, and smart grid control

Renewable power generation is one of the most important subjects in today's electricity production industy and in the future will dominate the agenda to remove power generation from the use of fossil fuels As priorities shift, a clearer understanding of renewable energy sources helps frame policy and investment decisions.

Of all the energy currently consumed in Canada, about 3,700 PJ (46%) is used to generate electricity. Canada has approximately 112 GW of installed electricity generation capacity, and produces approximately 561,805 GWh of electricity annually11 , resulting in a $27 B/yr business12 . Most electricity generation, transmission and distribution have traditionally been handled by vertically integrated provincial monopolies. This resulted in the construction of large-scale centralized power generation facilities and massive transmission systems owned by the same generator. The market is currently evolving under new deregulation guidelines. These shifts are framed by national discussions on renewable electricity policy and markets that influence provincial planning across Canada.

There are currently five main sources of power generation in Canada: natural gas, oil, coal, hydro (larger systems), and nuclear. The smallest component is from "other" sources (<2%), which includes renewable power generation. The National Energy Board estimates that "other" renewable power generation sources will reach 5.5 GW of installed capacity under the Business As Usual scenario, or 16.1 GW under the Techno-Vert scenario13, by the year 2025.Projection figures vary considerably throughout the industry and among government departments and jurisdictions,but are sufficient to provide a range from which to make some reasonable assessments. Contextualizing these categories against the spectrum of renewable power sources clarifies where incremental capacity is most likely to emerge.

Renewable Power Generation

Building on this theme, many jurisdictions measure progress by how much renewable power can reliably contribute during peak demand conditions.

Each sub-sector is examined for its potential to produce electricity and displace conventional fossil fuel electricity generation. Some of the fuels may have other - or even better - applications involving renewable power generation. Cross-sector comparisons with broader renewable alternative energy pathways can highlight complementary uses and integration strategies.

• Wind generated electricity
• Solar energy converted into electricity
• Stationary Fuel Cell technology that generates electric power
• Electric power generated from bio energy sources

• Wind Power: Wind power is becoming the leading non hydro-electric renewable energy source of North American electricity generation. The wind power industry, like the larger renewable power generation industry, has benefited from many years of public and private investment and technology improvements from countries around the world. As a result,some wind installations in Canada are now cost-competitive with (and even less expensive than) conventional electricity generation-even without the Wind Power Purchase Incentive (WPPI) program. Because there is lots of rural property in with suitable wind potential, it means there are many suitable locations which can support renewable power generation. The current focus of the wind power industry is to erect wind turbines and make them operational in time to meet future electricity demand.

• Solar PV Power: Solar energy is traditionally classified in three ways:Photovoltaics (solar electricity,or PV),Solar Thermal (heat) and Passive Solar (displacing the need for active heating or cooling). Most residential, commercial and industrial buildings require both electricity and heat (hot water,space heat,etc.). At this time,this report only focuses on Solar PV. If required,a full treatment of solar thermal (or the combined use of PV and solar thermal) may be conducted in a future analysis.
• Bio-electricity Power: Biofuels encompass all forms of renewable energy derived from bio-based matreials. Ttwo of the four types of renewable power generation from bioenergy sources are bio oil and bio gas. Bio oil can also be converted to electric power in means other than boiler combustion. Generally, bio-renewable power generation involves feedstock collection, fuel production and electricity generation.
• Stationary Fuel Cell Power (Hydrogen): Hydrogen as a possible renewable power generation source opens up a broad application area from alternative energy fuels in transportation to renewable power generation using special hydrogen fuel cells.While the application area for hydrogen is large,the specific focus of this report is on the use of hydrogen fuel cells for the delivery of renewable power generation to electricity grids.

Solid Biomass combustion is the most prominent form of biomass use in Canada. Biomass co-generation is already used widely in the pulp and paper industry for power, space and process heating. It is an established technology which needs improvement, but has not been a strong focus of biotechnology research and development. Advances in controls and co-firing are improving the competitiveness of biomass within the wider alternative energy power landscape for industrial sites.

The top five near-term investment opportunities for renewable power generation include:

Targeted pilots and standards can accelerate alternative energy development while de-risking capital for utilities and independent producers.

• Expanded Feedstock for Bio-electricity - To be successful, electrical generation (fuel conversion) equipment must be able to use a wider range of biomass feedstocks beyond the high quality sources that are currently used. Further, new logistics (collection, harvesting, refining) and conversion processes must be developed to supply a steady and reliable source of these additional raw materials for the emerging biofuel processes and bio-electricity facilities. Examples include technologies that go beyond corn-based ethanol8 and white-wood based pyrolysis.
• Wind Power Grid Integration Hardware - Connecting wind farms to the grid in a standardized,cost effective, and reliable way involves both new technology solutions and policy development. While grid connection is largely a policy issue, there are emerging technologies that can increase wind system power quality and reliability, which will help them gain acceptance among utilities.
• Liquid Biomass ( "Bio Oil") Plant Scale-Up - Demonstrations are required to validate the technical and economic viability of bio-processing plants as they scale from prototype to commercial sizes: ie: wood pyrolysis has progressed to the point of full production and needs to prove its value based on the many products that are derived.
• Large Wind Turbine Component - The wind power industry requires larger wind turbines to achieve energy economies of scale. However, to remain competitive in the renewable power generation business, certain ways must be explored to decrease the weight/power output ratio of wind turbines while at the same time increasing equipment life. It is being learned that new investments are required in the research and development of lighter, stronger and more cost-effective wind turbine components and tower designs.
• Solar PV Building Integration - Similar to wind, solar PV systems in Canada require greater access to the power grid.In the residential, commercial and industrial building markets there is the technical potential to fully integrate solar components within the structure and have it replace and reduce power demand from current sources. The cost of the solar power systems and their integration into renewable power development needs to be addressed. Many technological solutions and new energy policies may be required.

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Clean renewable energy powers electrification with solar, wind, and hydro, leveraging power electronics, energy storage, smart grids, and grid integration to cut carbon, enhance reliability, and optimize load management for sustainable electrical engineering.

What Is Clean Renewable Energy?

Clean renewable energy uses low-carbon sources and advanced grid tech to deliver sustainable electric power.

✅ Power electronics enable efficient conversion and control

✅ Energy storage stabilizes variable solar and wind output

✅ Smart grids and microgrids improve reliability and resilience

Clean Renewable Energy
Widespread use of clean renewable energy technologies (RET) is vital in securing a sustainable global energy system. Advantages of RET include:

• In contrast to conventional energy sources, the potential supply from renewables is essentially infinite and largely free of external costs.
• While clean renewable energy technologies currently still have relatively high installation costs, operating costs are low.
• In many countries, some RET are already competitive with conventional energy sources, for example biomass or biogas applications in Thailand. For most RET, costs will fall significantly below those of conventional energy sources within the next two decades.
• Increased use of renewable energy technologies is an insurance against rising import prices of fossil fuels.
• Renewable energy technology equipment can be produced domestically. For example, China has become one of the leading manufacturers of low-temperature solar thermal applications.

For readers comparing different technologies, this overview of renewable power sources outlines their characteristics and typical applications, aiding informed evaluation.

Given the mention of biomass competitiveness, this primer on biomass renewable energy explains feedstocks, conversion pathways, and typical project scales.

The number of countries where clean renewable energy technologies have seen significant market growth is steadily increasing. However,in most countries of the world, dissemination of new renewable energy technologies is still very limited. A range of barriers – financial, economic, institutional, political and technical – impede implementation. Key barriers include energy markets that are either monopolistic and skewed by subsidies, lack of energy awareness of renewable energy technologies potential and benefits, and a lack of technical and institutional capacity and financing means. So far only a few countries have implemented clean air energy policies promoting renewable energy technologies. To align stakeholders and policies, a concise primer on renewable energy fundamentals clarifies benefits, limitations, and common misconceptions.

Under the Kyoto Protocol, most public and private renewable energy project development companies can generate and market "certified emission reductions" from energy projects that involve renewable energy technologies that reduce carbon emissions in under developed areas of the world. The Kyoto Protocol provides financial incentives for shifting countries to less emissions-intensive economies. But while the Kyoto Protocol is able to lower some of the key barriers to renewable energy project development, especially in regard to the financial and economic aspects, it is not designed to cancel the obstacles. Adjusting these many conditions will attract more renewable energy technologies. These mechanisms can stimulate investment in renewable power projects across emerging markets, improving bankability and accelerating deployment.

Addressing the barriers that discriminate against renewable energy technologies in countries usually requires a mixture of well-designed and mutually supportive policies. Probably the leading issue is the economic performance of renewable energy technologies compared to the traditional energy sources that currently dominate the world's energy demand.There are two main approaches to addressing this central problem for developing renewable energy policies and technologies:

Effective policy design should reflect the maturity and grid-integration needs of different renewable energy sources so that incentives target real system constraints.

1. Bringing down the cost of renewable energy technologies and their related energy services 2. Abolishing market distortions that discriminate against the technologies Both approaches are reinforced by transparent market rules that value renewable electricity for its reliability contributions, flexibility, and environmental attributes.

Measures to address specific economic barriers include priority setting at project level by host countries, development of a suitable legal frameworks. This is not to say that Industrialised countries and the private sector cannot provide assistance such as building capacity and provding financing. But leading industrialized nations should provide international assistance to attract investment in renewable energy technologies. Clear definitions of what is renewable energy support coherent eligibility criteria and measurement frameworks in financing programs.

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Renewable energy projects optimize power systems with grid integration, solar PV, wind turbines, battery storage, inverters, and power electronics, enhancing smart grid reliability, microgrids, transmission, and distribution through modeling, protection, and control engineering.

What Are Renewable Energy Projects?

Projects that design, integrate, and control solar, wind, and storage for reliable, efficient electric power systems.

✅ Grid integration studies: load flow, stability, and protection schemes.

✅ Power electronics and inverter control for MPPT and grid codes.

✅ SCADA, forecasting, and storage optimization in microgrids.

Renewable Energy Projects seem to have survived the first cycle of the world economic recession. In fact, late 2008 and all of 2009 seemed better than many economists had recently expected. After a slowdown in world investment activity at the end of 2008, sustainable energy projects enjoyed a rebound during the final three quarters of 2010. For readers seeking a concise overview, the concept of what renewable energy is underpins these investment trends today.

The result was total new investment in worldwide Renewable Energy Projects reached about $162 billion in 2009, down slightly from the revised target of $173 billion for 2008. This was still the second highest annual figure ever recorded and nearly four times the total investment level of 2004. This performance demonstrated that Renewable Energy Projects were certainly not a typical bubble created by the so-called "credit boom", but was rather an investment story that will continue to be important for years to come. Understanding the mix of renewable energy sources helps explain the durability of capital flows in this sector.

The visual underscores how renewable power markets can rebound quickly when financing conditions stabilize.

While many policy-makers have increased their focus on encouraging the growth of Renewable Energy Projects, (partly to stimulate job creation and and offset the forces of recession) projects received new support. From the financial crisis of autumn 2008 until the spring of 2010, the world's chief economies set aside about $188 billion of “green stimulus” programs for Renewable Energy Projects. And since that time, the money has started to be spent. The United States recently announced a large grant scheme to assist the financing of renewable energy projects, and other countries followed the example of Germany, Spain and other European countries by commencing feed-in tariff programs to encourage and stimulate investment in Renewable Energy Projects.. Such measures are pivotal as governments scale clean renewable energy deployment across sectors and regions worldwide.

The major development banks, led by Germany’s KfW and the European Investment Bank, also became important actors in helping Renewable Energy Projects to weather the storm and expand into new markets. However, Renewable Energy Projects have often to cope with a bumpy path.

Blended finance vehicles increasingly target diverse renewable power sources to spread risk and accelerate grid integration across emerging markets.

The story of 2009, however, was one of resilience for Renewable Energy Projects. While there were areas of weakness such as project development in the US and finance for biofuel plants, there was also a decisive shift in the balance of investment towards developing countries and particularly China. Renewable Energy Projects in China was the strongest feature of the year by far, although there were other areas of strength in the world in 2009 such as offshore wind investment in the North Sea and the financing of power storage and electric vehicle technology companies. There was also a marked improvement in the cost competitiveness of renewable power generation compared to fossil-fuel electricity generation. These shifts align with fundamentals described in renewable energy facts that clarify cost trends and technology learning curves.

New investment in Renewable Energy Projects in 2009 was $162 billion, down from a revised $173 billion in 2008. The 7% fall reflected the impact of the recession on investment in Europe and North America in particular, with renewable energy projects and companies finding it harder to access finance:

• China saw a surge in investment in Renewable Energy Projects. Out of $119 billion invested worldwide by the financial sector in clean energy companies and utility-scale projects, $33.7 billion took place in China, up 53% on 2008. Financial investment in Europe was down 10% at $43.7 billion, while that in Asia and Oceania, at $40.8 billion, exceeded that in the Americas, at $32.3 billion, for the first time.
• Clean energy share prices rose almost 40% in 2009, reversing around a third of the losses they experienced in 2008. The WilderHill New Energy Global Innovation Index, or NEX, which tracks the performance of 88 sustainable energy stocks worldwide nearly doubled to 248.68 from its low of 132.03 reached on 9 March 2009.
• Major economies began to spend some of the estimated $188 billion in Renewable Energy Projects they announced in the months after the collapse of Lehman Brothers in September 2008. However the wheels of administration take time to turn, and even at the end of 2009, only some 9% of the money had been spent. Larger proportions of the stimulus funds are likely to be spent in 2010 and 2011.
• Total investment in Renewable Energy Projects by venture capital funds was $2.7 billion in 2009, down 36% on 2008. VC players found it harder to raise new money, because of general investor caution and because exits were hard to achieve given the weakness of stock markets.

Amid these fluctuations, the long-term outlook for renewable electricity remains strong given policy support and improving economics.

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Renewable energy systems integrate solar PV, wind turbines, battery storage, inverters, and smart grid controls for efficient generation, power conversion, and grid integration, enabling resilient microgrids and low-carbon, distributed electricity.

What Are Renewable Energy Systems?

Networks that convert renewable sources to grid-quality power using power electronics, storage, and control systems.

✅ Power electronics: inverters, converters, MPPT for PV and wind

✅ Grid integration: protection, synchronization, and power quality

✅ Energy storage: batteries, EMS, frequency and voltage support

Renewable energy systems today can be a cost effective alternative for areas with high electricity connection fees. For an overview of how stand-alone configurations work in remote areas, see this guide to off-grid solar power systems and typical cost considerations.

It is also possible to connect renewable energy power systems to the grid, reducing the amount of electricity you need to purchase, or in some cases, allowing you to export surplus power into the grid. Many homeowners start with a basic solar PV system to offset daytime loads before expanding capacity.

About renewable energy systems

Renewable energy is energy produced from sources which can be replenished or replaced from natural sources. For a deeper introduction, explore this overview of renewable energy and common technologies.

The most common forms of renewable energy used include:

• photovoltaic modules;
• wind turbine generators; and
• micro hydro generators.

Homes usually are serviced with electricity from any of these renewable energy systems on their own or in combination with other electric power systems. Resources on broader renewable alternative energy can help you compare options for your site.

Grid-interactive vs. stand-alone power supplies

Since renewable energy systems are often intermittent, (because solar panels only operate during daylight and mostly sunny days) a method of storing the electricity is required. The most common solution for this situation is to incorporate the use of storage batteries. Power from the solar array is used to charge batteries for use later in the day. Because these systems work independently from the electricity grid, they are often referred to as "stand alone power systems". In situations where the cost of connection to the power grid is prohibitive, a stand-alone renewable energy system can be cost effective. Many stand-alone systems use diesel or gasoline generators to recharge batteries during extended period without solar energy.

When planning capacity, it's helpful to weigh the pros and cons of solar power for your climate and usage profile.

An alternative is to use the electricity grid to store the energy. These systems are known as grid-interactive systems. The renewable energy is converted to electricity for use in the household and any surplus power is fed into the grid. Power is drawn from the grid when the renewable energy system is not enough to meet the home's energy demand. Some electric utilities prefer that all of the power from the solar power system is sent directly to the grid and metered separately , which means that all the electricity to the home comes from the grid as it is with conventional homes.

Components and features of stand-alone renewable energy systems.

Renewable energy systems consist of several very basic component equipment parts and there are key features which are briefly described and shown on this page.

1. Electric Power Generating Equipment
2. PV modules, wind turbines, micro-hydro generators, or a petrol or diesel generator can provide electric power production on their own or in concert with other systems.
3. Control and regulation equipment
4. Various types of power regulators, controllers, power meters and power circuit breakers may be used to control battery charging and to provide power protection.
5. Energy storage
6. Specialized large capacity batteries are usually used to store otherwise lost energy so that a reliable source of power can be available when needed.
7. Inverters
8. These devices convert electricity from the batteries or renewable energy source to the electricity used by household appliances (240 V AC).
9. Specialized “grid-interactive” inverters are able to feed electricity produced by renewable sources into the electricity grid without disruption to the household electricity supply.
10. Control Box
11. Wiring and electrical accessories

Well-designed renewable energy systems should include special wiring that is capable of keeping energy losses to an absolute minimum. Adequate power fusing, electrical grounding, lightning protection and other measures should be used in the renewable energy system.

• Home design, lighting and various appliances

   

  TNew home designs should incorporate useful energy efficiency features. Also, high efficienct lighting systems and appliances can be selected and specified to keep the energy load to a bare minimum, thus aiding to reduce the cost of such systems.

  Grid-interactive renewable energy power systems

  In addition to stand-alone systems, which require batteries to store energy, REPS can operate in conjunction with the mains electricity system. These are known as grid-interactive or grid-connected systems.

  How do they work?

  In grid-interactive renewable energy systems electricity is still generated from a renewable energy source in the same way as a stand-alone system. The electricity generated then passes through a specially approved power inverter, which converts electric energy into conventional 240 V which in turn is used by home appliances. When there is surplus electricity generated, it will be sent back through the inverter into the power grid. If the home consumes more electricity than your renewable energy system is producing, the power provider automatically will supply the balance of the energy required without any disruption to home appliances. Selecting a certified solar power inverter ensures grid compliance and optimal performance.

  Your power meter measures the level of outgoing and incoming electricity. This provides a net usage amount for your house. In the majority of cases, surplus electricity which is fed back to the electric utility is credited back to you. The net amount that is actual consumption is charged for that billing period. In reality, your power meter can become a cash register. Specialized "smart" meters are sometimes used where more detailed power monitoring is required. As there are variations to this process, check with your electricity supplier for more information on equipment and metering details for your property.

  What are the benefits?

  The major benefit of grid-interactive renewable energy systems is that they produce power from clean, renewable solar energy, allowing householders to reduce greenhouse gas emissions and improve our environment. As renewable energy systems use the main electricity grid as a back-up, power is always available and systems can be sized according to the customer’s requirements and budget. For background on technologies and policy, review renewable energy facts for informed decision-making.

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