Thermal vs Photovoltaic Solar

There are 2 different ways of harnessing the Sun’s energy – Thermal & Photovoltaics (PV)

Thermal technology is used for harnessing the heat radiation power of the sun. Typical applications include water heating & cooling, cooking and household/building heating.

Photovoltaics is technology that harnesses the energy of the sun and converts it into electricity and as such lends itself to many more applications – any electrical device, transport, stand alone systems etc.

Thermal systems are currently far more effective than their PV counterparts. PV efficiency rarely reaches above 15% where as thermal systems typically runs at around 80% efficiency. In fact a recent lab in the U.S. has produced PV cells that operate at around 25% – but at $10,000 per square centimeter no one will buy it.

That is why at Urban Solar all our systems are Thermal – the system is far more effective and the water in our geysers have been known to reach above 100 degress centigrade !!!! – VISIT OUR SITE

So when choosing a Solar System ensure that you know what functions you need it to perform and choose accordingly.

Have a Solar Day!

www.urban-solar.co.za

Electric vs Solar Water Heating….

The average household’s electric geyser consumes between 40% & 60% of total household consumption. The electric geyser is the single biggest user of electricity in the household.

Electricity costs have risen rapidly and will only continue to do so. Urban electricity costs per unit equate to approximately R0.77 per kWh if one factors in VAT & service fees (check your receipt next time), in fact 24% of every R1 you spend on purchasing electricity goes to VAT & Service Fees.

 

According to the latest reports (click here) Eskom is requesting 40% hikes in both 2010 and 2011. When this happens it will push electricity to R1.50 per kWh – nearly double the current prices.

 

 

Our system will displace on average around 10 kWh per day, electricity that would have been used from the grid is now being produced in your home. This will result in 2009 daily savings of R7.70, totalling R2818.20 over the entire year.

 

With the anticipated tariff increases in April 2010 of 40%, these figures jump to R10.78 daily and R3945.48 annually. The below table highlights the rapid increase in electricity tariffs and the associated costs of running an electric geyser since 2007.

 

 

SOLAR VS ELECTRIC GEYSER GRAPH

 

So the graph above is based on a R500 per month electricity at current 2009 prices. So the blue bars represents what you are paying now, have paid in the past and will pay in the future with continued use of an electric geyser.

 

The Red Bars highlight what your monthly electricity costs would be if you were using a solar water heating system given the 10 kwh daily displacement discussed above.

 

Have a Solar Day!

 

www.urban-solar.co.za

 

 

We have modelled the expected 40% increases for 2010 & 2011 to give some indication of where electricity costs are headed. At these levels expected system pay back is around 3.5 years.

 

 

 

 

 

 

 

 

 

 

Solar Energy in South Africa

Most areas in South Africa average more than 2 500 hours of sunshine per year, and average solar-radiation levels range between 4.5 and 6.5kWh/m2 in one day.

The southern African region, and in fact the whole of Africa, has sunshine all year round. The annual 24-hour global solar radiation average is about 220 W/m2 for South Africa, compared with about 150 W/m2 for parts of the USA, and about 100 W/m2 for Europe and the United Kingdom. This makes South Africa’s local resource one of the highest in the world.Water-heating accounts for between 30% to 60% of the energy consumption in the average household. In South Africa, this derives mainly from electricity, being the most common energy-carrier employed. Removing this expenditure could lead to significant improvements in the disposable incomes of homeowners.

 

The equivalent of a large coal-fired power station

(2 000MW+) is used to provide hot water on tap to the domestic sector alone. Since the inception of the accelerated domestic electrification programme through grid extension, a major distortion of the national load curve has emerged, with the early evening load peak growing significantly.

 

Modelling indicates that the introduction of solar water-heating can ameliorate the situation substantially. Switching from electrical to solar water-heating can, therefore, have significant economic and environmental benefits.

There are economic benefits for home owners in reducing their energy bills. Expensive generation capacity to address load peaks will be obviated, and the introduction of new base-load capacity will be postponed. Benefits for the country include reducing greenhouse gas (GHG) emissions, and the release of scarce capital for other pressing needs.

Solar water heaters have many benefits both for the customer and for South Africa. The customer benefits by having a reduced electricity bill and the country benefits because less power has to be generated by Eskom and so less pollution is generated.

 

So as you can see there are many advantages to Solar Power….

Whilst not everyone can afford to install one yet (we are working hard to make it affordable) there are other options that will start the progression to a more energy efficient South Africa.

Have a look at our energy and water efficient showerheads. They operate at a maximum of 9.5 litres per minute, compared to regular shower heads that range from 15 – 25 litres per minute. Not only do you save water and money you also save on the extra costs of heating that extra water. You can expect utility savings up to 60%.

Check it out @ http://www.urban-solar.co.za/shower-heads.html

Have a Solar Day

www.urban-solar.co.za

The use of solar energy is the most readily accessible resource in South Africa. It lends itself to a number of potential uses and the country’s solar-equipment industry is developing.