What is a Net-Zero Energy Building?

A zero-energy building (ZEB), also known as a net-zero energy building, emits no or very little carbon dioxide (NZEB). This shows that the amount of renewable energy generated on the property is equal to or greater than the annual energy consumption of the building. As a result of producing their own energy on-site, these buildings are largely independent of the national electricity grid.

Since the 1970s, there has been discussion about the idea of net-zero energy due to concerns about dependence on fossil fuels and petroleum shocks. These structures were built in accordance with environmental standards to address problems like climate change, resource depletion, pollution, ecology, and population growth. They are designed to have a much smaller detrimental ecological impact. They emit fewer greenhouse gases into the atmosphere.

The definitions of ZEBs differ in terms of the net energy inputs and outputs to balance the financial cost of energy used with the cost of equipment used in the structure for energy production. These highly effective structures have very low energy requirements, which are met by renewable energy sources. They make our living environment healthier for us. Because they consume less electricity than traditional structures, they help reduce carbon footprints.

Why Net-Zero Energy Buildings?

Over the past ten years, energy costs have increased along with growing worries about global warming and the quick depletion of fossil fuel resources. A lot of damage is caused by climate change. It is getting harder to find new fossil fuel deposits. Along with an increase in emissions and energy use, there are also other problems like health and well-being that can be solved by lowering carbon footprints.

Reducing emissions can be a good thing when it comes to tackling issues like climate change, ecology, and other environmental problems. Construction that is net-zero results in increased economic activity, more employment opportunities, and lower emissions and carbon footprints. A structure that has been designed sustainably will have less of an impact on the environment because of a better energy consumption strategy.

Key Features of Net-Zero Energy buildings:

Simply put, producing as much energy as is required for a structure for a year is what it means for a structure to be net zero in terms of energy. Although it is not difficult to build a net-zero home, it does require careful consideration, a systems-based approach, and greater upfront investment in high-quality, energy-efficient materials, machinery, and design. The expenses are worthwhile, though! Here are some essential characteristics of a zero-energy building.

1. Proper Orientation & Design:

An effective building’s orientation and design can help save a lot of energy. Using the building’s orientation in conjunction with climate responsiveness can reduce energy demand at a reasonable price. To save energy, these factors should be taken into account. The best materials for the structure should be chosen to save as much energy as possible.

2. Rainwater Harvesting System:

The core element of a rainwater collection system is a holding tank, which can be above or below ground. Utilizing gutters and downspouts, the tank collects rainwater from the roof. The tanks filter weeds, large sticks that resemble detritus, and leaves. The water is then sent by a pump to its intended use, which is frequently irrigation indoors but may also include flushing the toilet, washing dishes, or even providing drinking water after additional filtration.

3. Solar Technology:

One important technology for achieving net-zero energy buildings is solar/photovoltaic energy. The direct conversion of light into electrical energy is known as photovoltaic. Photovoltaic cells found in solar panels combine to create electricity. Due to their contribution to the cost disparity between net-zero and conventional construction methods, these solutions are regarded as sustainable and energy-producing. To build a functional net-zero building, these techniques require carefully thought-out strategies.

4. Energy-Efficient Appliances: 

Low-energy consumption and reduced energy load are two benefits of high-efficiency appliances. With the aid of such appliances, the energy produced onsite is guaranteed to operate as efficiently as possible. Energy efficiency is maximized as a result of minimizing energy use, making it a passive strategy. When energy is utilized effectively, well-designed buildings demonstrate sustainability.

Principles of Net-Energy Buildings:

The concept of Net-zero is enhanced by a variety of techniques and tools, including building orientation, shading, exposure, heat island reduction, lighting system, temperature, humidity, natural resources, landscaping, overall system efficiency, and many others. Following that, the designer should incorporate a life cycle analysis, net-zero water, and energy system, and optimize the design for occupancy levels. However, the following are the three guiding principles for effective net-zero energy building design:

1. Building Envelope Measures:

The conditioned interior of a building is physically separated from the unconditioned exterior environment by a building envelope. It is a significant element that affects how much energy a building uses. They are more than just some barriers; they are a system for the building that responds to its surroundings to create a comfortable environment while ultimately lowering its energy usage. 

A few measures for an energy-efficient building include using high thermal-resistant materials on the building’s facade, installing effective windows and door seals, reducing HVAC load, etc. The building’s ventilation system needs to be efficient enough to reduce infiltration. The building envelope measures should be applied in a manner consistent with the local climate. Depending on the location, a well-developed design strategy should be put into practice.

2. Energy Efficient Measures:

Having systems that are appropriate for the structure in terms of size is crucial for energy-efficient measures. By using variables that encourage the model to generate and forecast the requirements, it is possible to achieve this. A few examples of high-efficiency lighting and control systems that must be considered include daylight-dimming sensors, dual-circuited task lighting, high-performance ballasts, occupancy sensors, and daylight-dimming controls.

3. Renewable Energy Measures:

Energy can be maximized using the first two techniques mentioned above. It is believed that the cost of renewable energy measures is higher than the cost of the aforementioned measures. making responsible use of renewable energy sources, such as solar, wind, biomass, geothermal systems, etc. Solar technology allows for the generation of electricity and energy.

Wind energy is produced in a very economical manner. Using a biomass system, heat can be created and supplied by burning biomass materials such as agricultural wastes, wood chips, or pellets. Geothermal systems can be used for both cooling and heating because they don’t emit any pollutants when the refrigerant pipes are run underground.

Advantages

After considering all the potential future needs for a building, net-zero energy buildings are considered a practical and appealing investment. Due to their high energy production rates compared to actual energy consumption, they are environmental-friendly. However, have you considered their advantages? As such, the following are a few benefits of building with net-zero energy:

1. Better Reliability:

Net-zero energy buildings have better reliability when compared with traditional average buildings. The buildings have fuel cell-powered generators, so you won’t need to worry about blackouts, power spikes, or brownouts. Generators can be started in an emergency and will shut off automatically once the power is restored.

2. Economical in Long Run:

The owners and users of the net-zero energy building received their own set of advantages. These structures are thought to be more cost-effective in the long run than conventional structures. They are low maintenance, produce clean energy, and consume very little electricity. This is regarded as a sensible decision for a structure for its own sake.

3. Environmentally Compatible:

The net-zero energy system is environmentally friendly and sustainable. These buildings reduce greenhouse gas emissions. The net-zero energy building also depends on technology that allows it to use its resources more effectively than a regular building. This indicates that compared to other building types, net-zero energy structures have a reduced ecological impact.

4. Lower Emission of Carbon:

The net-zero energy building is not only considered to be more environmentally friendly but also to be a better choice for the environment. The area is a cleaner place to live in because there are few carbon emissions into the atmosphere. These structures generate significant financial savings because they consume less electricity than conventional structures.

5. Higher Resale Value:

The maintenance requirements of buildings built using energy-efficient technology will be reduced. Due to the increased value and desirability of net-zero energy structures, your property will cost significantly more due to the decreased maintenance requirements. Buildings with net-zero energy also have a higher resale value, which is an additional benefit.

Disadvantages

Net Zero Energy Buildings are an excellent method to lessen your carbon impact, but they might not be the best option for everyone. Before choosing whether or not a net-zero energy building is good for you, you should consider looking into the potential disadvantages that they have to offer.

1. Lack of Expertise:

Very few designers or builders possess the knowledge or expertise required to construct NZEBs. The staff for net zero energy buildings needs to be educated on the newest technology, and investment funds will need to be made in training initiatives that go by the wayside as many companies’ budgets get smaller.

2. Higher Initial Investment:

Net-zero energy construction has a significant cost disadvantage. Even though your initial costs would be somewhat higher, doing so would ultimately save you money. As the equipment’s parts require replacement on occasion, there are additional costs that will be associated with it. The value of capital invested in energy efficiency may decrease due to potential future drops in utility company renewable energy costs.

3. Accessibility & Reliability of Renewable Resources:

The absence of local renewable resources in net-zero energy buildings is another drawback. Long-term problems for the building may arise if you don’t produce your own renewable energy. Buildings that use zero net energy are thought to be more expensive than other types of structures. Net-zero energy buildings emit some carbon dioxide into the atmosphere, glass has a high embodied energy, and producing NZEB uses a lot of carbon.

4. The Grid:

There should be an on-site power plant or it should be connected to the grid to meet the requirements of renewable energy sources. It might not be wise to rely solely on oil and gas. Furthermore, when it comes to NZEBs, which emit fewer greenhouse gases but can’t be eliminated because the fossil fuel still produces it, less electricity is used.

Alternative Materials for NZEBs

Energy can be generated from photovoltaic panels and solar hot water panels for net zero energy buildings. To maximize the efficiency of the building you need to choose the right materials. We have an abundance of natural energy resources, where energy sourced from the sun and directed to solar panels helps generate energy to meet electricity requirements. 

The green roof can be considered an insulator as well as a cooling system for a building. To reduce the weight of the overall structure and minimize damage during natural calamities, glue-laminated timber, which has a low carbon footprint, is used in place of concrete and steel. For walls, hollow bricks made of concrete are used to handle moisture while also insulating.

A rainwater harvesting system is efficient because it reduces the cost of purchasing water from an outside source. Solar-integrated roof panels are a fantastic source of energy and electricity. The ability of a green plaster to absorb moisture from the air contributes to the building’s ability to maintain humidity.

The environment of the net-zero energy building is improved by natural ventilation, which brings direct natural air and light. A key component of net-zero energy buildings is a high-efficiency HVAC system. Building design elements like orientation, building envelope, lighting system, and appliances all have a direct impact on the size and energy use of the HVAC system.

Net-Zero Energy Building versus Green Building

Utilizing resources more wisely and minimizing a building’s harmful effects on the environment are the main objectives of green building and sustainable architecture. One important objective of zero-energy buildings is to reduce greenhouse gas emissions by exporting as much renewable energy as they consume annually. ZEB objectives must be established because they are essential to the design process. 

Zero-energy structures may or may not be deemed “green” in all respects, including waste reduction, the use of recycled materials, etc. In contrast to other “green” buildings that depend on imported energy and/or fossil fuels to function, zero-energy or net-zero buildings do have a much lower overall environmental impact throughout the building’s lifetime.

The practice of green building differs slightly from zero energy buildings in that it takes into account all environmental effects, such as resource use and water pollution, whereas zero energy buildings only take into account the building’s energy consumption and its capacity to generate an equivalent amount, or more, of energy from renewable sources. 

Green buildings can be broadly categorized as any structure that has a positive or negligible impact on the environment. Zero-energy buildings are specifically created to generate enough energy from renewable sources to meet their consumption requirements. Designers must look into all the factors while designing a specific building and also be careful while categorizing it.

Net-Zero Energy Buildings and The Grid

The majority of Net Zero Energy Buildings are still tethered to the electric grid, allowing for the use of traditional energy sources’ electricity (natural gas, electric, etc.) when they are unable to supply the building’s energy needs. Conversely, where permitted by law, excess energy produced on-site should be exported back to the utility grid when it exceeds the needs of the building.

A net energy consumption of zero results from excess energy production offsetting later periods of excess demand. Grid connection is typically required to enable the Net Zero Energy balance due to current technological limitations and cost constraints associated with energy storage. Project economics can be affected by differences in how utilities and jurisdictions handle the payment for energy exported from the building into the grid, so these issues should be carefully considered.

Applications

The majority of projects, including residential, industrial, and commercial buildings in both new and existing buildings, can benefit from the principles of net zero energy building. In all market segments and climate zones, an increasing number of projects have been planned and built. Here are a few examples of Net-Zero Energy commercial and residential projects:

1. Rajkumari Ratnavati Girls’ School, Rajasthan

Location: Jaisalmer, Rajasthan

2. SIERRA’S eFACiLiTY® Green Office Building

Location: Coimbatore, Tamil Nadu, India

3. Kalpana housing

Location: Auroville, Tamil Nadu

4. Humanscapes 

Location: Auroville, Tamil Nadu

5. Unnati 

Location: Greater Noida

6. Godrej Plant 13 Annexe

Location: Mumbai, Maharastra

7. Jaquar Headquarters

Location: Manesar, Haryana

Conclusion

Despite how big the obstacles are, it is known how to meet and overcome them. To maximize energy efficiency, we simply need to speed up the processes and get them to coordinate. We can achieve the objectives we’ve set for 2030 and 2040 if we apply this to both new and existing buildings. As we work to identify new, longer-term objectives, we may even be able to achieve those by 2050.