Ancho de cavidad

 Installation Of BIPV

As the title indicates, this part of the report gives a fair detail to the layman about how to install BIPV system and what are the basic components of the BIPV system

 How to install a BIPV system:

To install BIPV in newly constructing house or to the home already constructed the very first thing we need to decide that whether we need to fulfill all our electricity requirements by solar BIPV or to utilize BIPV as a substitute to the presently used conventional electricity. Once we have decided this, the very second step is to decide the capacity being installed accordingly, it needs a little knowledge of electrical terminologies otherwise we require to take the help of a consultant or directly the BIPV installers to calculate it.

Let‟s understand how to calculate the household power capacity required.

 Step-1: Calculate daily power used:

Method 1:

To do this, take the last 12 monthly power bills and calculate the average kilowatt hour (kWh) usage per month. The reason we use 12 is because our power consumption fluctuates with the seasons.

Then divide the monthly usage by 30 (the average number of days in a month, to get the daily power used.

So for example: If the monthly power consumption of 800 kWh (which is generally in a double story upper class 4 bhk house), then the daily consumption is 800/30= 26.7 kWh per day.

Now if we want to halve the power bill then you need to produce 26.7 / 2 = 13.4 kWh of solar panel watt power per day.

~ 48 ~ Method 2:

If we don‟t have the electricity bill then there is a way to calculate the power consumption by means of the electrical appliances used. All it needs to know is the capacity, hours of use and the hours of use per day of these equipments.

Some of these appliances with all the details are as given below: -

Sr no

Equipment Capacity Number Hours of use/day

Consumption /year

1 Tube-light 5-10 watts(taking 10w) 5 8hrs/day 146000 watt

2 Bulb 60 watts 5 4 hrs/day 438000 watt

3 Air-conditioner 1000 watts 1 4hrs/day 1060000 watt

4 Fan 10-50 watts (taking

30w)

4 8hrs 350400 watt

5 Computer 370 watts 1 8 hrs/day 1080400 watt

6 Television 100 watts 1 2hrs/day 73000 watt

Total 3147800 watt

= 3147.80 kw Table 4.2: Calculation of the per year consumption with the listed equipments

Source: Power consumption of equipments is taken from www.absak.com Power consumption per year = 3147.80 kWh (from table 3.1)

Power consumption per day = 3147.80/365 = 8.62 kWh Power consumption per hour = 7.66/24 = 0.359 kW

 Step 2 - Calculate total solar panel watt needs:

To do this, first determine how many usable hours of sunlight the area receives per day. This is taken from a solar insulation map.

For example sunshine hour per year in India = from 2300 to 3200 = 2750 (average) Thus average sunshine hours per day = 2750/365= 7.5 hours per day

~ 49 ~

Now we know the daily sunlight hours (i.e. 7.5 hours) and we have calculated per hour power consumption in Step1 (i.e. 13.4 kWh from method 1), thus if we divide the per hour power consumption by total sunshine hours in a day then we will get the power capacity required. This is calculated below:-

13.4 KWh / 7.5hrs = 1.78 kW or 1780 Watts

Thus 1.78kW is the power that we require for our house but since there are some energy losses from the solar panel watt wiring, battery, and inverter which is approximately 25% thus to get the desired power we need to install system which is capable of generating 1.78kW power with 25% energy losses. Thus the system would be 125% of the desired power.

Hence solar panel capacity should be: 1780*1.25 = 2225 watts

Now we are able to calculate the BIPV capacity that the house will require. After knowing this we need to calculate the cost of the BIPV system which requires the financial analysis of the 2.234 kW BIPV system which is being detailed out in a topic named financial analysis.

For a fair idea the general cost for a 2kW BIPV system could be around 8 lakhs with major of the cost required for PV module.

 Step 3 - Calculate solar panel watt costs

This step will help to work out the cost of the solar panels needed to make 2234 Watts of power. At the moment the lowest cost for solar panels based on multi-crystalline technology is Rs. 180 from the Indian manufacturer.

Since PV modules participate generally around 68% of the total cost of the BIPV system thus we can arrive at a rough estimate of the total BIPV cost that we are going to install. The detailed analysis of all these components and their financial part is described in the further part of the report - In our example: It will cost us at the most 2234 x Rs.180 = Rs. 4, 02,120 to install solar panels to halve our power bill.

~ 50 ~

Since this forms only around 68% of the system cost, thus the total system cost could be = Rs. 5, 91,352.9 which comes around Rs. 264.7/watt.

General cost breakup component-wise:

 Module: 68%  Inverter: 11%  Support structure: 7%  Mechanical work: 6%  Electrical work: 5%  Quality control: 3%

Source: ENVISION consulting report

 Step 4 - Offset tax credits and rebates

We need to take tax incentives and rebates in account which we get from the government and thus we need to deduct that from the initial amount.

With the BIPV installation subsidy of subsidy of 50% of module cost maximum up to Rs. 2, 00, 000. Hence 50% of module cost= 50% of Rs. 4, 02,120= Rs. 2, 01,060 would be paid by the government.

Source: MNRE website

Thus the price reduces to Rs. 5, 91,352.9 - Rs. 2, 01,060 = Rs. 3, 90,293 i.e. Rs. 174.7/watt Since there are many factors that go into calculating the solar panel watt costs, please only these steps as a rough estimate The above are the general steps which give a layman a fair idea on deciding whether to install BIPV system in the house or not.

~ 51 ~

4.6

Components of BIPV System

As we discussed earlier, A BIPV system typically have 4 basic components named as PV module, inverters, battery and BOS (balance of system). Given below we have discussed the description, technical and electronic details and some other information of all these components.

 PV module:

In the terms of photovoltaic, a photovoltaic module or photovoltaic panel is a packaged interconnected assembly of photovoltaic cells, also known as solar cells.. An installation of photovoltaic modules or panels is known as a photovoltaic array. Photovoltaic cells typically require protection from the environment. For cost and practicality reasons a number of cells are connected electrically and packaged in a photovoltaic module, while a collection of these modules that are mechanically fastened together, wired, and designed to be a field-installable unit, sometimes with a glass covering and a frame and backing made of metal, plastic or fiberglass, are known as a photovoltaic panel or simply solar panel.

Figure 4.4: Process of PV lamination While describing about the PV module the very common term being used is Photovoltaic cells known as PV cells or solar cells. Thus as mentioned below we have described about what is PV cell.

~ 52 ~

Figure 4.5: Types of PV modules

Module and cell efficiency:

Technology Thin films Crystalline silicon

A-SI CdTe CI(G)S A-si/µSi Dye s. cells mono multi Cell efficiency Module efficiency 4-7% 8-10% 7-11% 6-8% 2-4% 16-22% 13-19% 14-16% 12-15% Area neededPer KW(for modules) ~15m2 ~11m2 ~10m2 ~12m2 ~7m2 ~8m2

Table 4.3: Efficiencies of various cells and modules Source: EPIA report of September 2008

Solar PV technologies used in BIPV

Crystalline silicon solar cells Thin film solar cells

Mono crystalline PV modules Poly crystalline PV modules Copper indium diselenide PV PV modules Cadmium telluride PV modules Amorphous silicon PV modules

~ 53 ~

Lowest Prices PV Module ($/Wp):

Crystalline silicon (mono) $2.9/watt(DM solar)

A-si thin film $1.85/watt (Aten solar)

CdTe thin film $1.5/watt (first solar)

C(I)GS $6/watt(global solar)

A-si/µSi -

Dye s. cells -

Table 4.4 lowest prices of various PV modules

Photovoltaic cells are one of the most basic components of solar energy production. A solar cell or photovoltaic cell is a device that converts sunlight directly into electricity by the photovoltaic effect. Sometimes the term solar cell is used for devices that are intended specifically to capture energy from sunlight, while the term photovoltaic cell is used when the light source is unspecified. Assemblies of cells are used to make solar panels, solar modules, or photovoltaic arrays.

Photovoltaic is the field of technology and research related to the application of solar cells in producing electricity for practical use. The energy generated this way is an example of solar energy (also called solar power).

 Solar inverter:

A solar inverter is a type of electrical inverter that is made to change the direct current (DC) electricity from a photovoltaic array into alternating current (AC) for use with home appliances and possibly a utility grid.

Solar inverters may be classified into three broad types:

 Stand-alone inverters: used in isolated systems where the inverter draws its DC

energy from batteries charged by photovoltaic arrays and/or other sources, such as wind turbines, hydro turbines, or engine generators.

~ 54 ~

 Grid-tie inverters: which match phase with a utility-supplied sine wave. Grid-tie

inverters are designed to shut down automatically upon loss of utility supply, for safety reasons. They do not provide backup power during utility outages.

 Battery backup inverters: These are special inverters which are designed to draw

energy from a battery, manage the battery charge via an onboard charger, and export excess energy to the utility grid. These inverters are capable of supplying AC energy to selected loads during a utility outage, and are required to have anti-islanding protection.

 Battery:

A battery is an electric storage device, which can be found in any number of shapes, sizes, voltages and capacities. When two conducting materials (often-dissimilar metals) are immersed in a solution, an electrical potential will exist between them. If connected together through a closed circuit, a current will flow.

Batteries can be connected in series to achieve whatever voltage is required (add the number of 2 volt cells), and in parallel to achieve the capacity required (add the capacities of each parallel battery or string of batteries).

For larger systems, a number of series of strings may be connected in parallel with each other. This achieves both a higher voltage and capacity.

Series Wiring refers to connecting batteries to increase volts, but not amps. If you have two 6 volt batteries like the Trojan L16 rated at 350 amp hours, for example, by connecting the positive terminal of one battery to the negative terminal of the other, then you have series wired the two together. In this case, you now have a 12 volt battery and the rated 350 amps do not change. If you were to series wire four L16's you'd have 24 volts at 350 amps, and so on.

Parallel wiring refers to connecting batteries to increase amps, but not volts. If you have two 6 volt batteries like the Trojan L16 rated at 350 amp hours, for example, by connecting the

~ 55 ~

positive terminal of one battery to the positive terminal of the other, and the same with the negative terminal, then you have parallel wired the two together.

Batteries in parallel Batteries in series Batteries in series & parallel Fig 4.6: Series and parallel connection of solar batteries

 Charge controller:

Charge controllers, which protect battery from over charging and/or excessive discharge, are the essential component of Solar PV system.

Figure 4.7: Charge Controllers

A solar charge controller (or solar regulator) is an essential component of most solar charging systems over 10W. A charge controller protects your battery from overcharging and protects your panel from reverse current flow.

~ 56 ~

Components of solar charge controllers:

 TCB – PV combiner box

 Power Meters

 Battery Cables

 Ground Fault Protection

 Fuse Blocks & Fuses

Different types of charge controllers:-

 Controller up to 10 A

 Controller up to 30 A

 Dual solar controllers

 24 V solar controller

Charge controllers are sold to consumers as separate devices, often in conjunction with solar or wind power generators, for uses such as RV, boat, and off-the-grid home battery storage systems. In solar applications, charge controllers may also be called solar regulators.

Types of charge controllers: 1. Series charge controller 2. Shunt charge controller

A series charge controller or series regulator disables further current flow into batteries when they are full. A shunt charge controller or shunt regulator diverts excess electricity to an auxiliary or "shunt" load, such as an electric water heater, when batteries are full.

Simple charge controllers stop charging a battery when they exceed a set high voltage level, and re-enable charging when battery voltage drops back below that level.

~ 57 ~

Company Products/Services

Sunglow Energy Ltd. BIPV, solar power plants, hybrid energy, windfarms , biofuels Tata BP solar BIPV components

NYX Switchable glass, BIPV, e glass, led glass, speciality glass Solar-Apps Marketing, sales, distribution, solar, module, light, logistics,

technology, manufacturing, road studs, street light, BIPV, thin film, licensing

PV Power

Technologies Pvt Ltd

Solar panel, photovoltaic modules, BIPV

Inventure overseas inc

Solar boards, solar system, hand water pumps, solar pumps, solar led light kit, advertising and promotional material, balloons, inflatable, led lamps, water heaters, solar hoardings, bands, solar ups, water pumps, solar display box, solar for security

Alpex Exports Pvt Ltd Solar Panels, BIPV Solar Panels, Photovoltaic Table 4.5 List of BIPV suppliers in India Sources: Websites of the above mentioned companies

 Metering

 Net meter:

Net meter is a single meter which is used to measure in- and out-flow; the customer automatically receives compensation from the utility for any excess electricity produced at the full retail electricity rate.

Net metering is an electricity policy for consumers who own (generally small) renewable energy facilities, such as wind, solar power or home fuel cells. "Net", in this context, is used in the sense of meaning "what remains after deductions.

 Dual meter:

Without net meter, a small-solar system owner would be required to use two electric meters--one to measure electricity consumed from the grid, and the other, installed at the customer‟s expense, to measure any extra electricity sent back to the grid when the PV system produces more than needed.

~ 58 ~

4.7 Positioning of Panels

The direction and angle that the panel faces can have a big impact on its performance by affecting the amount of light that hits the panel each day through the year. Some solar panels move continuously to track the sun but most will not go to the expense and difficulty of implementing that.

To get it right we have to make sure that the panels get hit by the maximum amount of light. This happens when the sun is directly above the panel.

Figure 4.8: Ideal positioning of the solar panels

As you can see from above, the angle that the sun hits a panel changes the amount of exposure. At 30 degrees from the panel, the panel is only exposed to 50% of the light of the sun, at 60 degrees, 87% and at 90 degrees, 100%. This happens because the sun emits the same number of photons in a square cm, but once we put our panels on an angle, those photons are spread across a larger area.

As we all know, at different times of the day the sun moves through the sky and so any stationary panels get exposed to different angles, so what is directly above at one time of the day will not be at the next. What you might not know through is when the sun it at its highest it is not necessarily straight up, but may be off by an angle. And that angle is different at different times of the year and different at different latitudes. This angle is to the south in the northern hemisphere and the north in the southern hemisphere.

~ 59 ~

Figure 4.9: Movement of sun during the seasons

So we need to take all of this into account. Luckily what is good for your neighbor (aka your rough latitude), is good for you too. So below is a table that will show you what angles to have your panels on, at different latitudes, at different times of the year.

In document UNIVERSIDAD NACIONAL AGRARIA LA MOLINA (página 161-165)