Project Background
CCAT currently operates a work shop know as the greenshed which is currently being allocated as a space to design, build, and maintain appropriate technology projects. The Greenshed is located on the same property as the live-in CCAT center. This close proximity is very convenient, but it is being hindered by a lack of grid connected power. The Greenshed is in need of a light source powered which is not connected to the grid.
Shed Background
The CCAT green shed is approximately 18 ft x 10 ft with 180m2 of floor space.
Environmental Factors
Located in Arcata, Ca the site of the green shed has a variable amount of solar irradience, using the PVWATTS v.1 solar irradiance calculator it was determined that Arcata receives a yearly average of 4.48 hours of full sun a day. [1]
Problem statement
The objective of this project is to design and build a small solar array to light the green shed at CCAT. Currently the shed has no lighting source which severely limits the amount of work that can done within the shed. A functioning solar array will be used to show how small scale solar can be utilized to solve real world problems, this aligns with the demonstration goals of CCAT.
Project Criteria
Project Evaluation Criteria
The following Criteria will be used to assess the success of this project. These criteria were chosen based on the suggestions of the project coordinator as well as the diligent students who are working on the lighting system. The scale (1-10) represents the importance level of meeting the constraint of each listed criteria.
| Criteria | Constraints | Weight (1-10) |
|---|---|---|
| Maintainability | Must be easy to clean the filter and remove debris, no more than 2 hours maintenance per month | |
| Aesthetics | Must be pleasing to the eye and look professional | |
| Educational Aspect | Must include an educational piece for community | |
| Safety & Placement | Must be safe for use by CCAT staff and volunteers, must not interfere with work being done. | |
| Reproducibility | The structure could be reproduced by local builders | |
| Usability | Must sufficiently light tool shed. | |
| Budget | Must not exceed budget of $400 | |
| Functionality | Successfully produces and stores energy for use in shed. | |
| Lifetime | Must be usable for at least 5 years |
Tentative Time Line
| Project | Started | Completion |
|---|---|---|
| Calculate net sun for selected locations and determine collection panel placement. | February 20 | February 22 |
| Determine shed size | February 21 | February 21 |
| Using shed size determine desired lighting needs, price, and order lights | February 21 | February 22 |
| Determine max kWh the system can generate using panel size and calculated solar exposure | February 22 | March 22 |
| Using calculated system generation capacity, desired lighting time, and project budget, determine battery bank size | February 23 | March 1 |
| Price the rest of the system including mounts, wiring, switches, and necessary conduit | March 1 | March 8 |
| Order remaining system components | March 9 | March 16 |
| Install photovoltaic array | April 7 | April 12 |
| Link array to chosen light source | April 10 | April 16 |
| Test system to ensure proper working of all components | April 22 | May 3 |
Costs
The following table displays the projected costs for the Green Shed Solar Lighting project. Funding was provided by CCAT. The Panels were donated by Scurfield Solar in Arcata, Ca.
| Quantity | Material | Source | Cost ($) | Total ($) |
|---|---|---|---|---|
| 1 | Magnum MM-612AE 600 watt inverter | 479.00 | 0.00 | 0.00 |
| 3 | Light Bulbs | Arcata Recycling Center - The Reusables Depot Thrift Store | 14 | 14 |
| 1 | Bicycle Hub | Donated from Revolution | 0.00 | 0.00 |
| 1 | Blender Support Board | Salvaged | 0.00 | 0.00 |
| 1 | Blender Coupling | Angels of Hope Thrift Store | 0.55 | 0.55 |
| 1 | Misc Assembly Hardware (e.g.: screws, etc) | ACE Hardware | 1.47 | 1.47 |
| Total Cost | $5.02 | |||
Literature Review
The following is a concise synopsis of relevant literature reviewed for the comprehensive green shed lighting project at CCAT.
Solar basics
Paragraph on the basics. [2]
Applications of off grid solar
The lighting project for the green shed will demonstrate the manageability of a small off grid solar system. More than one in five people in the world live without electricity, off grid solar systems are an option that can be quickly installed in these areas and provide a base level of electricity. Currently people without electrical lighting mainly use kerosene lighting which is expensive and when used inside for long periods of time has adverse health effects including from the inhalation of toxins and fire risk. [3] [4]
Calculating Possible Solar Power
In order to calculate the power output of a solar system you need to know the amount of full sun hours received by your site, this value will vary over the course of a year but can be averaged. There are online calculators which are able to estimate this solar irradience value. After determining this value a solar path finder can be used to identify the most appropriate location on your site to place your panels.
Lighting options
There are many different lighting options that will need to be analyzed. These include a comparison of DC and AC lighting, incandescent, CFL, and LED bulbs. There is a range of criteria that these alternatives will be rated with that includes wattage, lifetime, and cost.
Calculating illumination needs
Calculating Illumination
Illumination can be calculated as
I = Ll Cu LLF / Al (1)
where
I = illumination (lux, lumen/m2)
Ll = lumens per lamp (lumen)
Cu = coefficient of utilation
LLF = light loss factor
Al = area per lamp (m2)
Energy Efficiency
Efficiency will be of great importance to this project for many reasons. These reason include the a reduced total system size, reduced carbon intensity of the system, and decreased system cost. Some efficiency measures such as LED lighting instead of CFL lighting may have a higher upfront cost , but this additional cost should be offset by their lower life cycle energy usage.[6]
Return On Investment
Because the energy generated by this system will offset energy that would otherwise have to be purchased by a grid provider, in this case PG&E, this system will generate revenue in the form of offset electricity cost. This offset electricity cost will help to recover the upfront cost of the system. The value of this energy offset can be calculated and compared to the upfront cost of the system to determine financially feasible project options.[7]
National Electric Code
Although it may not be of importance for this project to meet national electric code, the same standards will be used as a measure of quality assurance. The goal of these standards are to promote safe, reliable, and consistent results from photovoltaic power systems. [8]
Alternatives
Using the sun’s energy to illuminate the green shed is one of the many options available in terms of renewable energy. Similar projects could be achieved by taking advantage of other available resources such as wind, microhydro, or geothermal. Wave or tidal energy could potentially be harnessed as well, given that the location was close enough to the ocean. [9]
Off Grid Power
This photovoltaic system will exemplify the benefits of off grid power. Relief from rising electricity prices will be a benefit. Additionally, trends indicate that the current reliance on petroleum will cause future price increases. Off grid power offers security from these potential downfalls.[10][11]
References
- ↑ http://www.nrel.gov/rredc/pvwatts/site_specific.html
- ↑ Boxwell, Michael. 2010. Solar electricity handbook: a simple, practical guide to solar energy : designing and installing photovoltaic solar electric systems. Ryton on Dunsmore, Warwickshire, U.K.: Greenstream Pub.
- ↑ Bank, World. 2008. The Welfare Impact of Rural Electrification a Reassessment of the Costs and Benefits. Washington: World Bank. http://public.eblib.com/EBLPublic/PublicView.do?ptiID=459798.
- ↑ Njeri Wamukonya, Solar home system electrification as a viable technology option for Africa's development, Energy Policy, Volume 35, Issue 1, January 2007, Pages 6-14, ISSN 0301-4215, 10.1016/j.enpol.2005.08.019. (http://www.sciencedirect.com/science/article/pii/S0301421505002235)
- ↑ http://www.engineeringtoolbox.com/light-level-rooms-d_708.html
- ↑ Craig B. Smith, “Electrical Energy Management in Buildings,” in CRC Handbook of Energy Efficiency, ed. Frank Kreith et al. (Boca Raton: CRC Press, inc., 1997), 305.
- ↑ J. Kelleher and J.V. Ringwood, “A computational tool for evaluating the economics of solar and wind microgeneration of electricity,” Energy 34 (2009): 401, Accessed February 13,2013, doi:http://dx.doi.org/10.1016/j.energy.2008.10.009
- ↑ John Schaeffer, Solar Living Source Book: The Complete Guide To Renewable Energy Technologies & Sustainable Living (White River Junction: Chelsea Green Publishing Company, 2001), 504–505.
- ↑ Boyle, Godfrey. Renewable energy: power for a sustainable future. Oxford, England: Oxford University Press in association with the Open University, 1996.
- ↑ Boyle, Godfrey. Renewable energy: power for a sustainable future. Oxford, England: Oxford University Press in association with the Open University, 1996.
- ↑ Blackburn, John O.. The renewable energy alternative: how the United States and the world can prosper without nuclear energy or coal. Durham, N.C.: Duke University Press, 1987.