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European Journal of Applied Sciences – Vol. 11, No. 6
Publication Date: December 25, 2023
DOI:10.14738/aivp.116.15851
Attallah, S. & Shayesteh, A. (2023). Net Zero Energy Buildings and the cost per sf. European Journal of Applied Sciences, Vol -
11(6). 73-80.
Services for Science and Education – United Kingdom
Net Zero Energy Buildings and the cost per sf
Sherif Attallah
Department of Construction Management & Interior
Design, Ball State University, Muncie, IN
Alireza Shayesteh
School of Landscape Architecture, Ball State University,
Muncie, IN, United States
ABSTRACT
Zero energy buildings are created and constructed to use the least amount of energy
feasible [1]. These structures can produce enough energy to meet or surpass their
operating needs when a renewable energy source is added to them [1]. Most
modern buildings consume a lot of energy to run the lights, heat the water, chill the
air, and power personal electronics [2]. The large energy load will not be greatly
mitigated by adding solar systems. However, there are other structures that achieve
balance or even tilt the scales in the opposite direction. These are referred to as
zero energy structures. The reductions in energy use and carbon footprint must be
adjusted to account for real systems, such as the inhabitants and the local climate
before renovations may be advised on a continental scale [3]. According to Delavar
and Sahebi Energy is an essential resource for the economic growth of today's
businesses [4]. Residential and commercial buildings must utilize a significant
amount of energy to provide the services required. The total amount of energy
consumed in this industry has been constantly increasing. Due to the large
greenhouse gas emissions that arise, effective building management and energy
conservation have become top priorities for the energy and environmental sectors
all over the world. In this direction, net-zero energy buildings (NZEB) are a very
effective way to minimize energy consumption and alleviate environmental
impacts in buildings.
Keywords: net-zero energy, building performance, sustainable development, cost per
sqft, sustainable energy source.
INTRODUCTION
Global temperatures and carbon emissions have increased in the twenty-first century,
increasing the likelihood of environmental catastrophes. Energy management systems are
receiving more attention as a means of lowering greenhouse gas emissions because of the
global climate change challenge and growing environmental consciousness. The globe is
working to achieve the Millennium Sustainability Goals, which can help the planet get back to
how it normally is. In response to the anthropogenic issues, several companies that influence
the built environment have stepped up their efforts to prioritize sustainability. According to the
study done by Hakim et al building energy innovation is necessary because, as is commonly
noted in the literature, buildings in the United States use 40% of the country's primary energy
[5]. Therefore, designing buildings with energy efficiency in mind is essential to reducing the
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global carbon footprint and achieving sustainability goals. This includes using renewable
energy sources, implementing energy-efficient designs, and investing in energy-efficient
technology. Additionally, encouraging sustainable practices such as recycling, using natural
lighting, and utilizing green materials can also contribute to more sustainable building
practices.
A broad agreement on precise definitions of these buildings must be obtained for the NZE
concepts to take off in the market. The development of an effective design and control strategy
for NZE buildings would undoubtedly benefit from this agreement, which is also required for
assessing energy performance [6] [7]. This agreement must take into account the differences
between various types of buildings, climate and geographical conditions. It should also consider
the various materials used in the construction of the building and the impact of these materials
on its energy efficiency. Moreover, the agreement should cover the latest technologies to ensure
that the buildings are up-to-date and energy efficient. Lu et al. (2015) found that there is still
no uniform framework to define NZE buildings in the literature, and NZE is not a globally
accepted concept [7]. Research by Deng et al. titled "How to evaluate the performance of net
zero energy buildings" suggests that the definitions of NZE buildings should be clarified to
facilitate evaluation. There is no single standard expression for NZE buildings that is accepted
by the research community at the moment. Therefore, there is a need to develop a uniform
framework to define NZE buildings before any meaningful performance assessment can be
conducted. This framework should be based on consensus from the research community and
should be adapted to different climates and contexts. Therefore, the study stressed how crucial
it is to establish a framework that considers variables like border, metrics, climate, energy
sources, etc. Their research revealed that, within the established framework, individual
participants might define the definition's specifics. Numerous terms have been used
synonymously to describe this subject, including Zero Energy Building (ZEB), Net Zero Energy
Building (NZEB), Zero Net Energy (ZNE), Energy Neutral, and Energy Self Sufficient. The name
NZE building is used throughout the study to maintain a uniform vocabulary.
The U.S. Department of Energy's paper "A Common Definition for Zero Energy Buildings"
provides the following definition of NZE buildings as a whole: A "net zero energy building" is
one that is "energy efficient and whose real annual delivered energy, on a source energy basis,
is less than or equal to the on-site renewable exported energy" [9]. According to the DOE report,
on-site renewable energy systems are often located within the property boundary. It is
explained in the paper that a building does not meet these criteria for a NZE building if
renewable energy certificates (RECs) are used to offset the entire actual annual energy
consumption. The Renewable Energy Certificates (RECs) are tradable securities that can be
purchased to offset carbon dioxide emissions produced elsewhere. RECs may be purchased
voluntarily by buildings to increase their use of renewable energy. Leadership in Energy and
Environmental Design (LEED) offers points for the use of RECs in their scoring system.
Cost per square foot (sf) is an important factor to consider when evaluating NZE viability. There
has traditionally been a higher upfront cost associated with the construction of green or
sustainable structures. However, with advancements in technology and an increased demand
for energy-efficient buildings, the cost per square foot for NZEs has steadily decreased. The cost
per sf for NZEs can vary depending on several factors, including the location, size, design, and
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Attallah, S. & Shayesteh, A. (2023). Net Zero Energy Buildings and the cost per sf. European Journal of Applied Sciences, Vol - 11(6). 73-80.
URL: http://dx.doi.org/10.14738/aivp.116.15851
the technologies used. NZEs are generally more expensive to construct per square foot than
conventional buildings. There are additional costs associated with implementing energy- efficient features such as solar panels, high-performance insulation, energy-efficient HVAC
systems, and advanced lighting controls. The government and organizations have introduced a
variety of financial incentives and programs in order to further encourage the construction of
NZEs. By implementing these initiatives, builders and developers will be able to offset the
higher upfront costs of NZEs and make them more financially attractive. Examples of such
incentives include tax credits, grants, low-interest loans, and utility rebates.
LITERATURE SURVEY
Main Criteria for Net Zero Buildings
A handful of new structures have attained net zero energy. It has also been done in existing
buildings, albeit it is more difficult. The fact that massing, orientation, site design, and systems
are predefined and largely fixed distinguishes achieving net zero energy in an existing building
from doing so. Additionally, facility managers and occupants in older buildings may need to
adjust their operating expectations and usage patterns. It is important to not undervalue the
work necessary to alter tenant expectations and behavior, as well as their potential effects.
According to Carmichael et al. the likelihood of achieving net zero energy is highest in [10]:
Low-rise Buildings (one- or two-story):
Due to the restricted roof space for PV and the utilization of elevators, achieving net zero energy
in buildings with more than two stories becomes exponentially more challenging.
Moderate Climate Zones:
Severely humid regions, like Florida or the southern portions of Mississippi, as well as
extremely chilly regions, like North Dakota and the tip of Maine, make it more difficult to reach
net zero energy.
Buildings such as Warehouses:
loads (i.e., appliances, office equipment, computers). The energy sector is now dealing with a
few issues that are likely to get worse soon [4]. According to the International Energy Agency
(IEA), current energy sector behavior and carbon emissions have raised serious issues with the
environment, energy security, and economic growth [11]. Buildings contribute significantly to
global energy use and warming due to their long lifespans and greenhouse gas emissions,
necessitating appropriate interventions in this sector. A decrease in the environmental impacts
of buildings can have a significant positive impact on the environment, but there are few
effective ways to achieve this reduction. About 30% of CO2 emissions are attributed to building
energy use, whereas only 6% of all pollutants are attributed to household fuel consumption.
Building retrofitting and the deployment of effective renewable energy sources can lower
building energy demand, greenhouse gas emissions, and associated investment costs. Buildings
that use insulated materials store more energy than usual, so managing the in-and-out airflows
and insulation of the windows, walls, and ceilings to reduce energy consumption demand can
boost heat efficiency and comfort. On the other side, employing the right lighting, heating,
cooling, hot water, and energy systems and equipment in buildings can also lower the demand
for energy in the future. By reducing maintenance costs, gas emissions, increasing job
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opportunities, and improving health, building upgrading can increase energy efficiency.
Therefore, a sustainable future can be achieved by developing technology, changing, and
storing thermal pumps, merging heat-power systems, and utilizing renewable energy sources
with solar, wind, geothermal, and biomass technologies. Due to the high cost of these facilities,
it is important to properly balance the heat load, environmental performance, and expenses.
The life cycle cost (LCC), a benchmark that totals all building expenditures over a certain period,
can be used to determine the financial advantages of using energy resources during a
structure's usable lifespan. In contrast, the integrity of buildings can be thought of as a multi- criteria decision-making dilemma where the best goals can be the costs, the environment, and
other factors.
Ala and Reda study shows that in recent years, new concepts, and applications of Net- Zero/Positive-Energy Buildings and Districts (NZPEBD) have emerged because of the crucial
goal of decarbonizing towns and cities [12]. The NZPEBD research spans all relevant areas of
energy in buildings and communities, from the fundamental definition of the concept which
includes the definitions of the concept's boundary and the different kinds of energy credits to
the features of the building envelope, the components and integration of on-site renewable
energy systems, interactions with external grids, performance control and optimization, etc., as
well as social and economic issues.
Various social, political, and economic realms must be operationalized to achieve net zero [13].
There are many moral judgments, social concerns, political interests, fairness dimensions,
economic considerations, and technological transitions that must be navigated, as well as
several political, economic, legal, and behavioral pitfalls that could prevent the successful
implementation of net zero.
Considering Shanti and Torecellini paper, “A classification system based on renewable energy
supply options” building is classified as follow [14]:
Classification
Buildings Classified as NZE- A:
NZE: Energy is produced and consumed by a building by combining energy efficiency and re- gathered from inside the building's footprint. Due to their utilization of local RE resources,
these structures can be considered sites. Reaching a source or emissions NZE position may be
challenging if the source and emissions multipliers for a NZE: A are high during periods of utility
energy demand but low during periods when the NZE is exporting to the grid. Depending on
the local net metering regulations, it could be challenging to qualify as a cost NZE.
Buildings Classified as NZE- B:
Energy is produced and used by NZEB: B buildings through a combination of energy efficiency,
RE produced within the footprint, and RE produced on the site. Due to their utilization of local
RE resources, these structures can be considered sites. Reaching a source or emissions NZEB
position may be challenging if a NZEB: B's source and emissions multipliers are high when the
NZEB is consuming utility energy but low when it is exporting to the grid. Depending on the
local net metering regulations, it could be challenging to qualify as a cost NZEB.
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Attallah, S. & Shayesteh, A. (2023). Net Zero Energy Buildings and the cost per sf. European Journal of Applied Sciences, Vol - 11(6). 73-80.
URL: http://dx.doi.org/10.14738/aivp.116.15851
Buildings Classified as NZE- C:
As much as is practical, NZE:C buildings apply the RE techniques mentioned for NZE: A and/or
NZE: B buildings. Additionally, these structures make use of Option 3, which involves bringing
on-site renewable resources from outside the building. They might be considered NZEs for
sites, sources, and emissions since they make use of renewable resources. If carbon-neutral
renewables are employed, like wood chips, or if the source and carbon multipliers are not
favorable, it may be challenging to achieve a NZE:C source and emission situation. When a
utility has low source and carbon impacts and a NZE imports electricity when the utility has
high source and carbon impacts, this can happen. Because renewable resources must be
acquired and transported on site, NZE:C buildings often do not attain a cost NZE position. It
would be extremely difficult to recover these costs through any utility compensation for RE
generation.
Buildings Classified as NZE- D:
The energy strategies for NZE: A, NZE: B, and/or NZE:C buildings are used in NZE:D structures.
The greatest amount of on-site renewable methods is utilized. These structures also employ
Option 4, which involves buying certified off-site RE from certified sources, such as utility-scale
wind and RECs. Off-site options should be investigated, if necessary, after all cost-effective
efficiency and on-site RE measures have been completely utilized. If NZEB:D buildings purchase
enough RE and have favorable source and emissions factors, they may be eligible to become
source and emissions NZEs. They won't be eligible for site- and cost-based NZEs.
RESULT & DISCUSSION
History of this Approach to Building
In the past, climate ambition has either been expressed as a stable level of atmospheric
concentration or as an emissions reduction objective expressed as a percentage. Today, climate
ambition is most often defined as a precise deadline for achieving net-zero emissions, usually
related to the Paris Agreement's peak temperature goals. Net-zero targets have already been
reached for about two-thirds of world emissions and a somewhat more significant percentage
of global gross domestic product [15].
The idea of net zero is fundamentally scientific. Physics suggests that a finite budget of carbon
dioxide and other greenhouse gases are permitted into the atmosphere if the goal is to keep the
rise in world average temperatures within specific bounds. Any additional release must be
offset by removal into sinks after this budget has been reached.
Although a societal decision, the tolerable temperature rise is supported by climate science.
197 nations have committed to keeping global warming far below 2 °C and working to keep it
at 1.5 °C as part of the Paris Agreement. With a 50% chance of success, the 1.5 °C objectives can
be reached with a carbon budget of 400–800 GtCO2. To stay under this carbon budget, CO2
emissions must be peaked by 2030 and reach net zero by about 2050 [15].
Examples and Most Involved Countries
The eagerness with which an increasing number of nations, subnational institutions, and
individual organizations have made net-zero commitments attests to the narrative's capacity
to unite and inspire. We should support these pledges. However, there is a worry that these
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frequently voluntary promises may not be consistent with global net zero or aggressive climate
action since they permit too much choice in the design of net-zero routes. Therefore, actionable
commitments must be underpinned by a level of ambition that is in line with the Paris
Agreement. Additionally, it is essential to ensure that the commitments are monitored and
enforced in order to ensure they are delivered upon. Finally, there needs to be a transparent
system that measures the progress of these commitments and reviews them regularly.
Currently, there are insufficient procedures for governance, accountability, and reporting.
Often, long-term goals are not sufficiently supported by immediate activity. Many organizations
are vague about the use of carbon offsets in place of reducing their own emissions and have not
yet laid out specific plans to fulfill their commitments. The social and environmental integrity
of some of these offsets is under doubt. Because of this, some activists claim that these
commitments are merely "greenwashing" [15] Companies may be paying for carbon offsets
instead of actually reducing their emissions, which does not solve the underlying problem. This
practice can lead to a false sense that the company is doing something to fight climate change,
when in reality, it is only creating a Band-Aid solution.
In addition to the approximately 280 NZE emerging buildings that have been built for and
intended for net zero status but have not yet proven achievement of that aim, there are more
than 50 net zero energy (NZE) verified buildings in the United States. Simply put, an NZE
building uses no more energy than can be generated on-site through renewable sources over
the course of a year [5]. It is not surprising to observe a sharp rise in the number of NZE
buildings, given improvements in design, building methods, and technology. Another influence
is the growing number of US States and local governments requiring net zero buildings. The
number of confirmed and growing NZE buildings in the United States has tripled since 2012,
according to the New Building Institute (NBI).
The Cost Associated with the Net Zero Buildings
NZEs aim to reduce the amount of energy used from fossil fuels. With such a significant
potential, it seems pointless not to minimize the energy demand first. To reduce on-site energy
consumption, buildings should apply techniques in the building design, such as B.: daylighting,
insulation, passive solar heating, and natural ventilation, to name a few- ones. It was also
pointed out that energy efficiency measures such as high-performance windows, compact
fluorescent lights, water-cooled condenser air conditioning, and a highly insulated roof have a
combined payback period of slightly less than 15 years. This means that the initial investment
that is required for these energy-efficient measures will be returned through energy savings
within a relatively short period of time. Moreover, these measures can help to reduce carbon
emissions and improve air quality.
With current urbanization trends showing nearly 83% of Americans live in urban areas, the
need for energy-efficient homes that meet the growing density of cities explains the need for
multifamily housing across the country. The residential sector accounts for 21% of total energy
use in the United States. Efficiently built homes and apartments not only reduce greenhouse
gas emissions by using less energy but also provide tangible savings in energy costs that
building owners or tenants can appreciate. These energy savings can be achieved through
building design, energy efficient appliances, and smart energy management systems. Moreover,
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Attallah, S. & Shayesteh, A. (2023). Net Zero Energy Buildings and the cost per sf. European Journal of Applied Sciences, Vol - 11(6). 73-80.
URL: http://dx.doi.org/10.14738/aivp.116.15851
the cost of these energy efficient solutions can be offset by incentives from the government or
other organizations. These incentives can also make energy efficient solutions more attractive
to prospective tenants and buyers, which can help increase the value of the property. As a
result, energy efficient homes and apartments can be beneficial for both the environment and
the building owners or tenants.
According to the McKittrick and Gregor study, the analyzed EEMs (energy efficiency measures)
helped them reduce the buildings' total energy consumption with their baselines and models
[16]. Considering their model, which included different climate zones and types of buildings,
2,3,4 stories of residential buildings, they came up with the total building cost estimates. It is
estimated that for 2-story buildings, the cost/sqft is $173.55, contributing to $2,429,700 for the
total cost. For 3-story buildings, the cost/sqft is $165.84 with $3,482,550 and for 4-story
buildings is $183.48 with a total cost of $5,137,440. Overall, the cost is significantly higher for
higher stories, with a difference of $2,707,740 between the costs of 2 and 4 stories. These
estimates can help developers to plan their projects accordingly. It is important to consider
other factors such as labor costs, materials, and other expenses before starting a project.
Developers should also consider the potential return on investment of the project and the
expected duration of the project. Lastly, the quality of the construction should also be
considered.
References
[1] “Zero Energy Buildings Resource Hub.” Energy.gov, www.energy.gov/eere/buildings/zero energy- buildings-resource-hub
[2] “About Zero Energy Buildings.” Energy.gov, www.energy.gov/eere/buildings/about-zero-energy- buildings.
[3] Vinay, M.L. Real world energy and carbon costs of net-zero energy buildings. Commun Eng 1, 8 (2022).
https://doi.org/10.1038/s44172-022-00009-4
[4] Delavar, Hamed, and Hadi Sahebi. “A sustainable mathematical model for design of net zero energy
buildings.” Heliyon vol. 6,1 e03190. 15 Jan. 2020, doi: 10.1016/j.heliyon. 2020.e03190
[5] Hakim, Hamed & Asutosh, Ashish & Razkenari, Mohamad & Fenner, Andriel Evandro & Kibert, Charles.
(2018). A Study of Net Zero Energy Buildings in the U.S.: Evaluating Key Elements.
10.1061/9780784481301.047.
[6] IEA, S. Task 40/EBC Annex 52, Towards Net Zero Energy Solar Buildings, IEA SHC Task 40 and ECBCS
Annex 52.
[7] Lu, Y., Wang, S., & Shan, K. (2015). Review: Design optimization and optimal control of grid-connected and
standalone nearly/net zero energy buildings. Applied Energy, 155463-477. doi:
10.1016/j.apenergy.2015.06.007
[8] Deng, S., Wang, R., & Dai, Y. (2014). Review: How to evaluate performance of net zero energy building-A
literature research. Energy, 711-16. doi: 10.1016/j.energy.2014.05.007
[9] Peterson, K., Torcellini, P., Grant, R., Taylor, C., Punjabi, S., & Diamond, R. (2015). Common definition for
zero energy buildings. US Department of Energy
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[10] Carmichael, Cara, and Katrina Managan. "Reinventing existing Buildings: eight steps to net ZeRo eneRgy."
Institute for Building Efficiency an Initiative of Johnson Controls: Milwaukee, WI, USA (2013).
[11] Paul Waide, Daniele Gerundino, International standards to develop and promote energy efficiency and
renewable energy sources. Prepared for the G8 Plan of Action. IEA Information Paper, 2007, p. 2011.
Retrieved March 28.
[12] Hasan, Ala, and Francesco Reda. 2022. "Special Issue “Net-Zero/Positive Energy Buildings and Districts”"
Buildings 12, no. 3: 382. https://doi.org/10.3390/buildings12030382
[13] Fankhauser, S., Smith, S.M., Allen, M. et al. The meaning of net zero and how to get it right. Nat. Clim. Chang.
12, 15–21 (2022). https://doi.org/10.1038/s41558-021-01245-w
[14] Pless, Shanti, and Paul Torcellini. Net-zero energy buildings: A classification system based on renewable
energy supply options. No. NREL/TP-550-44586. National Renewable Energy Lab. (NREL), Golden, CO
(United States), 2010.
[15] Fankhauser, S., Smith, S.M., Allen, M. et al. The meaning of net zero and how to get it right. Nat. Clim. Chang.
12, 15–21 (2022). https://doi.org/10.1038/s41558-021-01245-w
[16] McKittrick, Adam R., and Gregor P. Henze. "Cost analysis of annual and monthly Net zero energy
performance for Multifamily buildings in the United States." Journal of Architectural Engineering 27.
NREL/JA-5500-79217 (2021).