Solar+Panels

=Middlebury SD Guide to PV Systems=

__**Mapping Solar Potential**__

Helpful (and wicked awesome) Resources developed by Efficiency Vermont using GIS: []

__**PV and Comprehensive Energy Budget**__

Basic Terms:
 * kWh (kilowatt hour)
 * measure of energy (like a calorie)
 * kW (kilowatt)
 * measure of power or rate of energy (energy/time)
 * equivalent to kilajoules/second
 * energy sources produce kWh of energy
 * energy demand measured in kWh/yr or kWh/month etc..

How does a PV panel work? - Each photovoltaic cell within a solar panel utilizes the photoelectric effect to turn sunlight into Direct Current (DC) electricity • Semiconductors within the cells absorb photons of light and release electrons, which are then captured to create an electric circuit •DC power is converted to AC power via a "Inverter" (at 95% efficiency)

How does a PV system work? • Individual solar panels are grouped together into an array • Inverter: converts DC power produced by solar array into AC power used by the standard electric grid •Energy flows to meter connected to Fusebox and appliances in the house •Energy not used during the day, can be sent back to the Electrical Grid (AKA Net-Metering) •At night, power is bought back from the Grid at an off-peak price

PV Types: __**A. Mono/Polycrystalline Silicon**__ __**B. Building-Integrated Photovoltaic (BIPV)**__ __**C. Thin-film Photovoltaic (CdTe, CIGS, Amorphous silicon)**__

Solar Panel Angels: Things to consider
 * Latitude of Site
 * Middlebury
 * Irvine
 * Type of PV Mounting
 * Tracking
 * Adjustable
 * Fixed
 * Seasonal Variability in Sun Angles
 * Summer
 * Spring/Fall
 * Winter

Optimum Seasonal Solar Panel Angles:
 * Site and Latitude || Optimum Angle Winter || Optimum angle Spring and Autumn || Optimum Angle Summer ||
 * Irvine, CA 33o N || 60.5 || 32.5 || 8.0 ||
 * Middlebury, VT 44o N || 69.5 || 42.5 || 17.0 ||

Possible Energy Budget: • Self Reliance estimates ~627 kWh per month • EIA estimates ~666 kWh per month • Array should be around ~7.5 kW • Roof Space: 18 ft by 28 ft • Sunpower E20/327 panels are 5.15 ft by 3.43 ft (~23 panels on current roof plan+room for solar water collector) • Would be 7.5 kW array - Contingent on appliances etc..

Energy Breakdown:
 * kitchen
 * dishwashing: 75 kWh/yr
 * refrigeration: 450 kWh/yr
 * cooking: 297 kWh/yr
 * laundry
 * washing: 32 kWh/yr
 * drying: 518 kWh/yr
 * other
 * lighting: 95 kWh/yr
 * consumer electronics: 131 kWh/yr
 * small appliances: 148 kWh/yr
 * auxiliary appliances: 490 kWh/yr

Outline:
I. Complete PV Systems and Components > A. Crystalline Silicon (c-Si) Modules/Systems > B. Thin-Film Modules/Systems > C. BIPV (Building Integrated Photovoltaics) II. PV Installation
 * 1) Solar Panels (PV Modules)
 * 1) Inverters
 * 2) Mounting/Racking System
 * 3) Combiner Box
 * 4) AC/DC Disconnect Switch
 * 5) Service Panel

=Link to Introduction to PV Technology=

To look into:

Optimal Solar Panel Tilt:Pay attention to the seasons and adjust according to the latitude the home is located... -If your latitude is between 25° and 50°, then the best tilt angle for summer is the latitude, times 0.93, minus 21 degrees. The best tilt angle for winter is the latitude, times 0.875, plus 19.2 degrees.

=__I. Complete PV Systems__=

Consists of: Solar Panels (PV Modules__)__ Inverters Mounting System Combiner Box AC/DC Disconnect Switch Service Panel


 * __1. SOLAR PANELS__**

There are a variety of factors to consider when choosing solar/PV panels and modules, most importantly, density (efficiency/area or wattage/area--for best use of limited rooftop space) and price (for obvious reasons). **EFFICIENCY IS NOT THAT IMPORTANT**--it is density which actually tells us the space efficiency of the module, and modules with higher efficiency are often disproportionately priced compared to lower efficiency modules**!** Space is also not a major constraint (below we see teams with total kW of 6.3 kW to 10.9 kW winning full scores in Energy Balance). Thus, **price should be our major criterion** in which panels to use. Secondary factors are appearance and the ease of installation, though these are factors which do not have the absolute impact that price does.

Below is a chart of the Energy Balance contest scores and rankings in the 2011 competition. (DC Rating) || Inv. Quant. || Inverter kW (Max DC Input) || Inverter kW (Max Rec. DC Power @STC) || Inverter kW (AC Rating) || Sanyo HIT Double 195 (1.17 kW) || 6.69 || 1 1 || None None || 6.250 2.000 kWp || 5 kW 1.5 kW || (3 sub-arrays) || 8.2 || 2 1 || None || None || 5 kW 5 kW || Bosch (1.38 kW) || 4.1 || 1 1 || 3.159 ? 2.160 ? || 3.750 2.500 || 3.0 kW 2.0 kW || It is easy to derive that the choice of PV module and the total kW of the system does not show any strong or direct correlation with Energy Balance scores. However, the relationship between the Maximum Recommended DC Power Input (second-to-last column) and the total array kW seems to play a significant role in team's final scores. All of the teams in the top 10, 7 of which received the full score of 100, and none of which received below 83 points, had inverters whose maximum recommended DC power far exceeded the kW of the array. The same effect is seen in the bottom six teams in the contest--four of five teams (we have no information for one team) had system kW which exceeded or barely met the maximum recommended input of the inverters. Three of them scored zero, and the other team only earned a meager 3.590 points out of 100. The inverters of choice overwhelmingly were manufactured by SMA, which produces Sunny Boy inverters as well as the Sunpower-branded inverters. SMA, a German-based manufacturer, is the leading inverter company in the world.
 * Team || Score || Ranking || PV Module || Array kW
 * New Zealand || 100 || 1st || Mitsubishi PV-UJ225GA6 || 6.3 || 1 || 6.35 || 7.500 || 6.0 ||
 * Purdue || 100 || 1st || Sunpower E19/238 || 8.6 || 1 || None || 10.000 || 8 ||
 * Tennessee || 100 || 1st || Solyndra SL-001-182 || 10.9 || 2 || None || 11.520 (5.760 x 2) ? || 10.0 kW ||
 * Florida Int'l || 100 || 1st || Sunpower 315E-WHT-D || 8.96 || 2 || 8.48 (4.24 x 2) || 10.00 (5.00 x 2) || 8.10 ||
 * Maryland || 100 || 1st || Sanyo Hit Power 220A || 9.24 || 42 || None || 10.08 (0.24 x 42) || 8.82 ||
 * Illinois || 100 || 1st || Sunpower E18/230 (5.52 kW)
 * SCI-Arc/Caltech || 100 || 1st || Hanwha Solarone SF-160 || 7.98 || 1 || 7.400 || 8.750 || 7 ||
 * Massachusetts || 96.160 || 2nd || Sunpower E19/240 || 6.72 || 2 || None || 9.80 (4.90 x 2) ? || 7.8 kW ||
 * Ohio State || 88.586 || 3rd || First Solar 77.5 W || 8.37 || 1 || 7.400 || 8.750 || 7 ||
 * Middlebury || 83.229 || 4th || Sunpower 225 || 6.75 || 1 || None (7.400) || 8.750 || 7 ||
 * Canada || 56.013 || 5th || Conergy P-235PA || 8.70 || 19 || None || 4.37 (0.23 x 19) || 7.22 kW ||
 * Appalachian State || 36.580 || 6th || Sanyo HIT Double 195
 * Parsons NS Stevens || 35.169 || 7th || Yingli YL260C || 4.16 || 1 || 4.0-6.3 kWp || None || 5.1 ||
 * China || 3.590 || 8th || Sanyo HIT Power 220A || 8.8 || 1 || 8.600 || 10.000 || 7.68 kW ||
 * Florida || 0 || Last || SolarWorld || 5.06 || 11 || None || 2.53 || 4.18 kW ||
 * Tidewater Virginia || 0 || Last || Sanyo (2.65 kW)
 * New Jersey || 0 || Last || Petra Suntech 225 System || 8.8 || 40 (BUILT-IN) || FLUNK ||  || 8.0 kW ||
 * Belgium || 0 || Last || Sanyo HIT Power 215 || 7.74 || 1 || 4.200 || 5.000 || 4 kW ||
 * New York || 0 || Last || Sunpower E19/238 || 9.52 || 40 || None || 9.60 (0.24*40) || 8.40 ||

Worthy to note is that in the 2009 Net Metering contest (since replaced with the Energy Balance contest), the top three teams in the Net Metering contest all opted to use Sunpower panels. That same year, two of the five teams which received a Net Metering score of zero used Sanyo HIT modules. The first-place German team added CIGS panels from GeneCIS to the wall exterior as well. Notably, Sunpower modules also have the [|highest density], meaning efficiency/area, of all manufacturers, followed by Sanyo. (We do not suggest relying on the above link for calculations, only for quick reference.)

The above modules in 2011's competition also cover a large range of efficiencies and densities, all of which have no strong correlation with the final Energy Balance scores and rankings. Thus, to conclude, unless we have significant space constraints on our roof compared to other contestants, price should be our key criterion when deciding on the solar panels to utilize on our project. As long as the PV manufacturer is reputable and the product is reliable and well-tested, our performance in the Energy Balance contest will be positive with whatever product we choose. A better price for the panels can give us extra points in the Affordability contest, as well as Market Appeal. When we analyze price, what really matters is price per kilowatt-hour, not price per watt. However, it is difficult for us to simulate conditions and future maintenance and operation costs, and predict the price per kWh over the years--thus, price per watt may still be the best number to make our decision upon.

On the other hand, solar modules are at their lowest price in a decade, with many modules selling for just under $1/W. Thus, while price should still be a major criterion, the overall impact may not be as significant as two year ago, where solar modules cost three to four times more their current price. The only major module manufacturer that has kept their prices higher is Sunpower, which charges closer to $1.60/W. Thus, although we mentioned the excellent performance of Sunpower modules above, the large price difference may still not be a worthy investment for the competition.

Below we compare different solar modules from manufacturers around the world.


 * Company || Material || Price || Efficiency || HQ || Product Origin || Website ||
 * SunPower || c-Si ||  || 20.1% || US || US || [] ||
 * Westinghouse || c-Si ||  ||   || US || US ||   ||
 * Kyocera || Poly c-Si ||  ||   || JP || Worldwide ||   ||
 * AUO Solar || c-Si ||  ||   || TW || TW ||   ||
 * Motech || c-Si ||  ||   || TW || US, CN, TW ||   ||
 * Nanosolar || CIGS ||  ||   || US || US ||   ||
 * Suntech || Pluto Cell,Silicon ||  || 14.4%-19.9% || CN ||   || [] ||
 * Alta Devices || gallium arsenide ||  || 28.6% || US || US || http://physicsworld.com/cws/article/news/2012/apr/26/quirky-solar-cell-sets-new-efficiency-record ||

__** Alta Devices **__ -Prototypes are 28.6% efficient! -Light-emitting solar cells. Instead of overheating like other solar cells, it emits heat. -Made with gallium arsenide (the arsenic becomes inert when bonded to gallium, so it's not dangerous) -Being produced on an industrial scale and shipping samples to consumers now. -Commercial shipment should take place by the end of 2013. [] [] []

-Mimics the shape and function of vertical growing ivy by using a vast array of "solar-leaves" -Highest wattage per leaf is 4kwh (yet leaf is made with chemicals) -Organic solar panels use less chemicals and are biodegradable (only .5Kwh) http://solarivy.com/solarIvy_productSheet_062211.
 * __Solar Ivy__**

-Modular solar canopy which can provide shade while also producing solar electricity -Shape can be contorted to give different shading with transparent canopy @http://tensilesolar.com/
 * __Solar Canopy__**

Characteristics: Most common material for solar panels, most efficient conversion factor, most cost-efficient as well
 * __A. c-Si Modules (Crystalline Silicon)__**

- High efficiency colored solar panels - 14-15% efficiency - Colored to blend in with rooftop design (Green for the green-roof) - Company based out of Taiwan, offered sponsorship for colorized panels []
 * LOF Solar Corporation**

-18-19% efficiency -Black modules blend in with shingling of roof design (don't stick out) -SunPower solar panels outperform competitors in low-light conditions, generating solar power even on cloudy days. - 320 square feet of their E20 panels will allow for a peak generation of ~6kW. []
 * SunPower: High Efficiency Panels**

**Westinghouse Solar **
- Can directly deliver AC power instead of inversion from DC power source - Integrated connection, racking, and wiring system (makes installation a lot simpler) - Available from 195-235 watt solar panels @http://www.westinghousesolar.com/index.php/products/64-residential-products

- Cheap and extremely efficient - Up to 16% efficiency - Available from 135-315 Watts @http://www.kyocerasolar.com/residential-solutions/solar-panels/current-products.htm
 * Kyocera KD Solar Model**

- Also include direct delivery of AC power, like Westinghouse - Co-produces world's highest efficiency module with SunPower - http://solar.auo.com/?sn=784&lang=en-US&c=238
 * AUO Solar**

- Acquired GE Energy module production lines in Delaware - http://www.motechsolar.com/products/modules.aspx?view=all
 * Motech**


 * __B. Thin-Film PV Modules__**

- Ranging from 180W to 240W, three times more power per panel than standard thin-film panels. - Mainly used for utility scale buildings - Highly efficient yet more expensive Info at http://www.nanosolar.com/technology/product-specifications =__BIPV Windows__= Building-Integrated Photovoltaics(BIPV) are windows that have PV integrated within the layers of the window.
 * Nanosolar: Thin-film solar panels.**

[[image:middleburyresearch/Screen_shot_2012-03-20_at_1.27.56_AM.png]]
[]
 * =====**Efficiency up to 16.9%!!!**=====
 * SunEwat photovoltaic modules comply with the aesthetic and functional requirements necessary for perfect integration in buildings and replace materials that are currently used.
 * Cell-to-cell spacing can be changed to allow versatility in the light transmission of the module.
 * SunEwat is custom-built, providing architects with a lot of flexibility in the design of facades, canopies, sunshades, balustrades, etc. - while also featuring built-in electricity generation.
 * Using SunEwat photovoltaic modules enhances the building's environmental image.

sales.uk@eu.agc-group.com

>
 * Pythagoras Solar PV WINDOWS**
 * Efficiency of 12% conversion
 * Designed to replace conventional windows and are INSULATED
 * Customized to any size
 * Allows seasonal and daily energy efficiency optimization

source: []

'solar roof tiles' which replace conventional roofing (roof tiles, shingles, etc.). Source [|here]

Dow Chemical Company, [|Dow Powerhouse Solar Shingles] • CIGS (Copper, Indium, Gallium, Selenium) thin-film panels that are 10-13% efficient • However, these shingles are expensive (~$10 square foot), and not that efficient compared to a standard array (3.5 kW/1000 square feet) • These or other shingles could be used as an auxiliary power source, like on a porch canopy, but alone they would not be able to produce the kind of power we need because they require 30-50% more roof area to produce the same amount of energy as a standard silicon panel array.

Other solar shingles include

[|Atlantis Energy System Sunslates] (22 watts/panel; 50 panels/100 square feet) The same limitations that apply to the Powerhouse system also apply to Sunslates

Atlantis Energy Systems also produces the [|B.I.T.E.R.S.] (Building Integrated Thermal Electric Roofing System) array, which has both power generating and thermal features.

[|www.solarbuzz.com] - a good website for looking at solar technology and the solar industry

[] Different way to orient solar panels based on leaf formation and the Fibonacci Sequence

Dye solar cell technology "artificial photosynthesis" lower cost and embodied energy in manufacture, can be directly incorporated into buildings manufactured by Dyesol []

[] Interesting hybrid pv/thermal

Environmentally friendly solar panels, using fewer chemicals and 9.8% efficiency []

New prototype by Semprius, record-breaking efficiency. May not be applicable to a house of such small scale [] []

UNDER CONSTRUCTION
Types of solar panels with attached company names: CdTe ([|First Solar] and [|Abound]) to CIGS ([|MiaSolé]) to CIS ([|Solar Frontier]) to GaAs ([|Alta Devices]) to triple-junction CPV cells ([|Solar Junction] and [|Semprius]) to crystalline silicon ([|SunPower] and Suntech).