Grantee Research Project Results

Final Report: Sustainable Responsivity: The Integration of Nanosolar Skin for Built Environment and Mobility

EPA Grant Number: SU835701
Title: Sustainable Responsivity: The Integration of Nanosolar Skin for Built Environment and Mobility
Investigators: Azarbayjani, Mona , Oloonabadi, Maryam Ahmadi , Zarrabi, Amir Hosseinzadeh , Cohen, Daniel , Kassel, Jennifer , Ren, Keming , Walter, Michael , Pike, Victoria
Institution: University of North Carolina at Charlotte
EPA Project Officer: Hahn, Intaek
Phase: I
Project Period: August 15, 2014 through August 14, 2015
Project Amount: $15,000
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet (2014) RFA Text |  Recipients Lists
Research Category: Pollution Prevention/Sustainable Development , P3 Awards , P3 Challenge Area - Air Quality , P3 Challenge Area - Sustainable and Healthy Communities , Sustainable and Healthy Communities

Objective:

The primary objectives of the nano skin façade design research were as follows:

1. Developing the nanoscale responsive skin material, and carry out a performance assessment in the area of energy demands and energy production potential.
2. Investigate the possibility of integrating the prototype in different forms and applications of building façades, and mobility because they offer novel approaches for solar-toelectric energy conversion leading to high-efficiency devices via simple manufacturing and transportation. The nano solar skin thin film does not block the views and does not impact on the aesthetics aspects.
3. Fabricate a 1:1 nano solar skin prototype developed from performance-based design strategy.

Summary/Accomplishments (Outputs/Outcomes):

The goal of Phase I was to develop the methods and equipment needed to develop the material and evaluate its performance in generating solar power and reducing the energy loads. The team was able to develop of the materials and equipment needed to grow the silicon microwire array solar cells using chemical vapor deposition (CVD) processes. In addition, energy efficiency modeling was done to evaluate the proposed technology and preliminary heat gain reduction measurements were performed to evaluate the materials performance.

 

Our major challenge was develop and assemble all the equipment and methods needed to synthesize the silicon wire films in a short period of time and begin the process of scaling up the thin film production. We were able to successfully build the silicon wire reactor chamber and have been able to develop the cleanroom processes needed to prepare the patterned substrates. We are currently optimizing our process for growing the silicon wire substrates and have been engineering various designs for integrating the polymer materials needed for embedding the wires in a flexible support.

The energy used to offset unwanted heat losses and gains through windows in residential and commercial buildings cost the United States $20 billion (one-fourth of all the energy used for space heating and cooling) in the year 1990. In recent years, windows have undergone a technological revolution. High-performance, energy-efficient window and glazing systems are now available that can dramatically cut energy consumption and pollution sources. In residential, skin-load dominated structures (such as housing) optimum window design and glazing specification can reduce energy consumption from 10%-50% below accepted practice in most climates. In internal-load dominated commercial, industrial, and institutional buildings, properly specified fenestration systems have the potential to reduce lighting and HVAC costs 10%-40%.¹As shown in table below, the U value and solar heat gain coefficient of the product is compared to the available technologies such as building integrated photovoltaic films to reduce heat gain and electrochromic devices.

 

 

	U-Value	SHGC (Solar Heat Gain Coefficient)	Tvis(Visual Transmittance)	Max η (Solar Conversion Efficiency)	Initial Cost ($/ft2)	Application
Low-E	0.26– 0.352	0.273– 0.62	53%4- 74%4	NA	42 5	Integrated
BIPV	0.16 – 0.24	0.16 – 0.38	16%6- 28%6	8.37 – 13.58	57 9	Integrated
Electrochromic	0.15– 0.35	0.055– 0.55	2% 10 - 70% 5	NA*	80 5	Integrated
Nano Solar Skin	0.2 – 0.3	0.1– 0.5	10% - 80%	5 - 10	80-100	Integrated

 

Table 1. Comparison of properties of different technologies similar to nano solar skin

 

By incorporating sunlight when its cool outside and blocking it when its hot, the energy use and other expenses associated with operating a building will be minimized. The US Department of Energy estimates that tintable window systems are capable of providing up to:

• 20% savings in operating costs

• 24% reduction in peak demand

• 25% decrease in the size of HVAC systems

In addition, the National Renewable Energy Laboratory (NREL) says that if all buildings used products like electrochromic windows, we could save about 5% of the nations total energy budget each year. This is equivalent to saving more than 160 gigawatts of electricity from fossil fuel-burning plants. Not only the solar responsive nano solar skin materials will minimize the peak demand and the operating cost but it will also generate electricity.

Conclusions:

Sustainable development's three pillars focus on the goals of P3: Planet, Prosperity and People. These were three fundamentals of our approach to the project. By integrating nano solar skin in buildings, as DOE's National Renewable Energy Laboratory have said that full deployment of dynamic, highly insulating glazing can save up to five percent of the US energy budget. That's equivalent to over 160 gigawatts of electricity generated annually by fossil fuels. Such savings could reduce CO₂emissions by 300 million metric tons. The benefits to planet are significant. In addition, nano solar skin uses a byproduct of the silicon manufacturing processes such as those used in the semiconductor industry, which will improve it's environmental cycle. Providing abundant daylight and views of outdoors, regulating the heat that enters the space and reducing the glare, increases the occupant's well being. Nano solar skin embraces natural light without blocking the views and by blocking the unwanted solar heat gain it preserve the comfort of the occupants. Following the development of the nanomaterial, our next task is to figure out the power generation technology and engineering that and to scale this product up and commercialize it for building façade use.

Journal Articles:

No journal articles submitted with this report: View all 5 publications for this project

Supplemental Keywords:

Energy efficiency, green buildings, façade, nano solar skin, daylighting technology, integrated design, performance-based design, Energy, sustainability.

Relevant Websites:

Integrated Design Research Lab Exit

Nanoscale Science Ph.D. Program Exit

Office ofEnergy Efficiency & Renewable Energy