Portsmouth Sustainable Energy & Climate Change Centre - PSECC

Facilitaors for Climate Change Mitigation  - Renewable Energy Technologies, Advice, Grants & funding.


PSECC has been formed to provide advice, support and guidance on Climate Change, Global Warming, Renewable Energy, Grants and Funding provision for the people of Portsmouth, Portsmouth & Hampshire Council’s, Governments, schools, colleges, Commercial & International clients. 

Do not leave Global Warming to others, we must do more, energy efficiency also Renewable Energy - Solar PV, Biomass, Wind & Water Turbines, Carbon Capture & Storage & Nuclear, do we risk limited action, can we take the risk?? NO

Solar for Homes, Schools and Commercial Clients

Cut those Energy Bills & make extra revenue from Solar PV !!!!

Save on Energy Bills and also receive full revenue from Solar PV Feed-In-Tariff - funding available


Solar PV can add more than 14% to property value (source: Department of Energy and Climate Change

New research published by the Department of Energy and Climate Change (DECC) has revealed that energy saving improvements could add significant value to properties across England.

According to DECC, improving a property’s EPC rating from band G to E or from band D to B could add more than £16,000 to the sale price of the average property in England.



We provide:




Cut CO2 emissions

reduce Global Warming  & Climate Change


The UK Government have established the Feed-In-Tariff (FIT) which enables Private Residents to have technologies such as Solar PV panels installed.  There are financial benefits to the FIT and Solar PV for residents: saving on electrical bills and revenues from the FIT. 

Many Solar companies are offering Free Solar PV Installation to home owners, PSECC “Do Not” recommend this type of offer as all of the FIT goes to the installation company over a 20 year period, which could amount to as much as £21,415, a loss to the Residential home owner, Housing Association or Council .


Our team is waiting


Commercial Clients of PSECC - Lakeside Cosham in Portsmouth


250KW system for Lakeside in Portsmouth

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PSECC has arranged Solar Pv for six schools in Hampshire as part of their Hampshire county Council work - Renewable Energy in Schools 2010





Warren Park


Mark Rutherford



PSECC - launch a Social Enterprise initiative called Leigh Park Solar & £COM in the Leigh Park area in Havant near Portsmouth, Hampshire UK.

This project aims to switch customers who had a FREE installation of Solar PV to a NEW scheme that allows them both to save on electricity bills and also receive the revenue from the Feed-In-Tariiff with no extra cash outlay. Also we hope to bring renewable energy to all council tenants, lowering their electricity bill by between £40 & £80 per month and allowing the Portsmouth City Council who own the homes to make a revenue of over £100 million over 25 years if they install Solar PV on 5,000 Council owned homes. Also Solar Farms will be discussed and hopefully developed in the area so all council tenants can have this free electricity source. Negotiations are underway for this exciting potential project and it is hoped will result in a tender being issued for the Solar PV installation work. PSECC can arrange all funding requirements, if required at an interest rate of between 3.5% & 4%. £COM - a Community shop will be opened and part of any revenue stream from the Solar PV will be channeled back into a community fund to enable poorer residents to have affordable loans for Home appliances such as washing machines, fridges, cookers, beds and TV’s together with being able to purchase clothing at a much reduced rate. Also paining & decorating services will be offered on a voluntary basis. Leighpark Solar will also produce many jobs for local residents.

In order to raise educational levels of attainment Laptop computers will be sold at around the £100 mark. With a fairer scheme of energy use and generation in the Leighpark are then it is hoped that crime, drink and drug misuse may be some what reduced.

PV Mounting Systems & Tracking Devices

PV- modules are either added to existing buildings, integrated into new buildings or installed as free-standing structures in a field. Where they are free-standing, they can also be fitted on moving platforms tracking the angle of the sun.

Building- applied modules (BAPV)

In many cases, pv- systems can be retro-fitted to buildings, either on tilted or flat roofs.


Tilted Roofs

A number of mounting systems have been developed specifically for PV- modules on tilted roofs such that no major building work has to be undertaken. The modules tend to be made from aluminium and can grip onto the roof tiles.

The crucial characteristics of these systems are:

Snow Load: Weight that the structure is able to carry.

Wind Speed: Wind between the roof and the panels can create a significant force. Some mounting systems may therefore be limited to low-wind zones only.

Roof Slope: Most mounting systems will not allow roof tilt angles higher than 60°.

Lightning Protection: It is essential that the mounting system comes with lightning protection.

Naturally, orientation of the roof is important. Ideally, facing due south at an angle of latitude - 10% - 25%.


Flat Roofs

Flat roofs provide an ideal space for solar systems, as these are often unused spaces. Moreover, flat roofs don't have the limitations of the pre-existing orientation of tilted roofs. In fact, in the U.S. alone, in excess of 100million square meters of reflective roofs are installed annually. Commercial rooftops in the U.S. alone could provide an average of 5GW!

On flat roofs, flat panels are installed at a fixed tilt angle, similar to stand-alone pv- installations. However, this option may not be feasible if the panels would be too heavy or if there is too much wind, which may affect the stability of the tilted up panels.

Solyndra, an American company, provided an alternative which was a thin film module in cylindrical shape. Although of lower efficiency, they were lighter and not susceptible to wind. Thin film is wrapped around cylinders. As a result, light can be collected from anyn angles, rendering tilting unnecessary. In addition, the thin film may also catch light that has been reflected off the roof itself. Due to its unique geometry, there are also no issues with wind activity. However, Solyndra filed for bankruptcy in 2011.


Building- integrated modules (BIPV)


There are many shapes and forms where pv panels, especially roll-on thin films can be used in buildings.

Some of the major characteristics are:

Colour of the surface. Unlike crystalline photovoltaics, thin film pv does not necessarily have to be blue.

Transparency: Some thin films are transparent to the visible spectrum. This way they can be put on big window fronts of office blocks, and still generating some electricity while not blocking the light for the offices inside.

Flexibility: Some panels come protected with glass while others are more like sheets

Free-standing Modules and Tracking Devices


Free-standing modules can be mounted such that they face the best angle. Again, wind speeds need to be taken into account. With some mounting systems, the manufacturer advises to place the modules flat on the ground during wind storms.

Unlike on tilted roofs, stand-alone solar installations can make use of tracking platforms that can tilt the surface along one or two axis with the help of a motor. The motor itself is connected to a device that determines the angle of the sun. Not surprisingly, tracking provides a significant energy boost. However, this comes at a cost, as the tracking mechanics are more expensive. The energy requirement for the motors on the other hand is negligible.

To avoid these additional costs, a good compromise would be for the mounting system with only one axis (azimuth) to allow two tilt angles, one optimised for summer, the other for winter (Seasonal Tilt). The customer can change the angle manually according to season.

Automated tracking can be passive or active. Due to thermal inertia, passive systems tend to be slow in changing from the sunset position to the sunrise position. Active trackers either calculate the current position of the sun from first principles, or use light sensors that will point the modules to the brightest point in the sky, not necessarily the sun - especially when it is cloudy.


Effect of Tracking Devices

Tracking will always result in a higher energy yield. The amount of the boost however is very much dependant on the location. Generally, locations with a higher proportion of direct sunlight such as Spain or Finnland will benefit more from tracking than locations with a high proportion of diffuse light such as Germany.


Tracking increases the performance ratio of a system. It also results in higher yields for the inverter. In addtion, shadowing is greatly reduced.

Flat Panel - horizontal surface

Fixed mounting, optimum angle

1-axis tracking

1-axis with seasonal adjustment

2- axes tracking

Energy boost in comparison to optimum tilt






Initial marginal cost per m2





Solar Power Technologies

There are two ways of converting solar radiation into electric energy:

§  Photovoltaics (PV): In certain materials, absorbed light is directly converted into electricity (photo-effect)

§  Concentrated Solar Thermal (CST): Here, direct light is focused into one point in order to heat a liquid. The heat is subsequently used to drive a generator like in a conventional power station.

Solar Power Technologies

There are two ways of converting solar radiation into electric energy:

Photovoltaics (PV): In certain materials, absorbed light is directly converted into electricity (photo-effect)

Concentrated Solar Thermal (CST): Here, direct light is focused into one point in order to heat a liquid. The heat is subsequently used to drive a generator like in a conventional power station.


We are using a number of measures to describe solar modules:




Rated Power


Maximum power the system is capable of delivering. This is also called the nominal power.

Peak Power


This is the power a module delivers if subjected to a standard radiation (Am-1.5) of 1kW/m².

Cell Efficiency


Rate at which the semiconductor cell converts energy from radiation into electricity.

Module Efficiency


As several cells are connected to form a module, there are additional losses stemming from the wiring. Note that there is no difference between cells and modules in thin-film technology.

Capacity Factor


With respect to a specific installation, the capacity factor is the average power delivered over a year compared to the rated power. Hence, it is a measure of the actual output compared to the output it could deliver.

Reasons why the capacity factor is less than a 100%:

§  Variance in solar irradiance: darkness during night, clouds etc.

§  Downtime due to maintenance

§  Non-optimal optimal operation due to panels not clean or not free from snow.

§  The System is oversized for the given location.

What is solar PV system?

Solar photovoltaic system or Solar power system is one of renewable energy system which uses PV modules to convert sunlight into electricity. The electricity generated can be either stored or used directly, fed back into grid line or combined with one or more other electricity generators or more renewable energy source. Solar PV system is very reliable and clean source of electricity that can suit a wide range of applications such as residence, industry, agriculture, livestock, etc.

Major system components

Solar PV system includes different components that should be selected according to your system type, site location and applications. The major components for solar PV system are solar charge controller, inverter, battery bank, auxiliary energy sources and loads (appliances).

  •   PV module – converts sunlight into DC electricity.
  •   Solar charge controller – regulates the voltage and current coming from the PV panels going to
      battery and prevents battery overcharging and prolongs the battery life.
  •   Inverter – converts DC output of PV panels or wind turbine into a clean AC current for AC
      appliances or fed back into grid line.
  •   Battery – stores energy for supplying to electrical appliances when there is a demand.
  •   Load – is electrical appliances that connected to solar PV system such as lights, radio, TV, computer,
      refrigerator, etc.
  •   Auxiliary energy sources - is diesel generator or other renewable energy sources.

Solar PV system sizing

1.    Determine power consumption demands


The first step in designing a solar PV system is to find out the total power and energy consumption of all loads that need to be supplied by the solar PV system as follows:

     1.1 Calculate total Watt-hours per day for each appliance used.
           Add the Watt-hours needed for all appliances together to get the total Watt-hours per day which
           must be delivered to the appliances.

     1.2 Calculate total Watt-hours per day needed from the PV modules.
            Multiply the total appliances Watt-hours per day times 1.3 (the energy lost in the system) to get
            the total Watt-hours per day which must be provided by the panels.

2.    Size the PV modules


Different size of PV modules will produce different amount of power. To find out the sizing of PV module, the total peak watt produced needs. The peak watt (Wp) produced depends on size of the PV module and climate of site location. We have to consider “panel generation factor” which is different in each site location. For Thailand, the panel generation factor is 3.43. To determine the sizing of PV modules, calculate as follows:

     2.1 Calculate the total Watt-peak rating needed for PV modules
           Divide the total Watt-hours per day needed from the PV modules (from item 1.2) by 3.43 to get   
           the total Watt-peak rating needed for the PV panels needed to operate the appliances.

     2.2 Calculate the number of PV panels for the system
           Divide the answer obtained in item 2.1 by the rated output Watt-peak of the PV modules available
           to you. Increase any fractional part of result to the next highest full number and that will be the
           number of PV modules required.

Result of the calculation is the minimum number of PV panels. If more PV modules are installed, the system will perform better and battery life will be improved. If fewer PV modules are used, the system may not work at all during cloudy periods and battery life will be shortened.


3. Inverter sizing


An inverter is used in the system where AC power output is needed. The input rating of the inverter should never be lower than the total watt of appliances. The inverter must have the same nominal voltage as your battery.

For stand-alone systems, the inverter must be large enough to handle the total amount of Watts you will be using at one time. The inverter size should be 25-30% bigger than total Watts of appliances. In case of appliance type is motor or compressor then inverter size should be minimum 3 times the capacity of those appliances and must be added to the inverter capacity to handle surge current during starting.

For grid tie systems or grid connected systems, the input rating of the inverter should be same as PV array rating to allow for safe and efficient operation.

4. Battery sizing


The battery type recommended for using in solar PV system is deep cycle battery. Deep cycle battery is specifically designed for to be discharged to low energy level and rapid recharged or cycle charged and discharged day after day for years. The battery should be large enough to store sufficient energy to operate the appliances at night and cloudy days. To find out the size of battery, calculate as follows:

     4.1 Calculate total Watt-hours per day used by appliances.
     4.2 Divide the total Watt-hours per day used by 0.85 for battery loss.
     4.3 Divide the answer obtained in item 4.2 by 0.6 for depth of discharge.
     4.4 Divide the answer obtained in item 4.3 by the nominal battery voltage.
     4.5 Multiply the answer obtained in item 4.4 with days of autonomy (the number of days that you
           need the system to operate when there is no power produced by PV panels) to get the required
           Ampere-hour capacity of deep-cycle batter

Battery Capacity (Ah) = Total Watt-hours per day used by appliances x Days of autonomy
(0.85 x 0.6 x nominal battery voltage)

5. Solar charge controller sizing


The solar charge controller is typically rated against Amperage and Voltage capacities. Select the solar charge controller to match the voltage of PV array and batteries and then identify which type of solar charge controller is right for your application. Make sure that solar charge controller has enough capacity to handle the current from PV array.

For the series charge controller type, the sizing of controller depends on the total PV input current which is delivered to the controller and also depends on PV panel configuration (series or parallel configuration).

According to standard practice, the sizing of solar charge controller is to take the short circuit current (Isc) of the PV array, and multiply it by 1.3

Solar charge controller rating = Total short circuit current of PV array x 1.3

Remark: For MPPT charge controller sizing will be different. (See Basics of MPPT Charge Controller)

Example: A house has the following electrical appliance usage:

  • One 18 Watt fluorescent lamp with electronic ballast used 4 hours per day.
  • One 60 Watt fan used for 2 hours per day.
  • One 75 Watt refrigerator that runs 24 hours per day with compressor run 12 hours and off 12 hours.

The system will be powered by 12 Vdc, 110 Wp PV module.

1. Determine power consumption demands

Total appliance use = (18 W x 4 hours) + (60 W x 2 hours) + (75 W x 24 x 0.5 hours) = 1,092 Wh/day

Total PV panels energy needed          = 1,092 x 1.3

                                                         = 1,419.6 Wh/day.

2. Size the PV panel

2.1 Total Wp of PV panel capacity    = 1,419.6 / 3.4


2.2  Number of PV panels needed      = 413.9 Wp

                                                         = 413.9 / 110

                   = 3.76 modules

          • Actual requirement = 4 modules
             So this system should be powered by at least 4 modules of 110 Wp PV module.

3. Inverter sizing

    Total Watt of all appliances = 18 + 60 + 75 = 153 W
    For safety, the inverter should be considered 25-30% bigger size.

    The inverter size should be about 190 W or greater.

4. Battery sizing

    Total appliances use = (18 W x 4 hours) + (60 W x 2 hours) + (75 W x 12 hours)
    Nominal battery voltage = 12 V

    Days of autonomy = 3 days

    Battery capacity = [(18 W x 4 hours) + (60 W x 2 hours) + (75 W x 12 hours)] x 3
                                                (0.85 x 0.6 x 12)

    Total Ampere-hours required 535.29 Ah
    So the battery should be rated 12 V 600 Ah for 3 day autonomy.

5. Solar charge controller sizing

    PV module specification
    Pm = 110 Wp
    Vm = 16.7 Vdc
    Im = 6.6 A
    Voc = 20.7 A
    Isc = 7.5 A
    Solar charge controller rating = (4 strings x 7.5 A) x 1.3 = 39 A
    So the solar charge controller should be rated 40 A at 12 V or greater.


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