So, you’re planning on going solar?
This is a great option for a number of reasons. After all, solar is an amazing renewable resource that is very effective at powering a home. As more and more people make the transition from traditional power sources to greener options such as solar and wind power, there is a great deal more information out there to help one prepare. Although the choice in itself is one that will pay off in great rewards both environmentally and financially, there is a learning curve involved.
It is this learning curve for which you need to prepare your family. When you do go solar, you will need the cooperation and understanding of the whole family to make it work best.
People turn to solar energy for several reasons. A little preparation will go a long way to make your transition from conventional energy to solar energy as trouble-free and worthwhile as possible. How you should prepare for it depends on your goals and expectations.
Going solar out of environmental consciousness
A large percent of people who convert to total solar energy are motivated by their commitment to use an environmentally friendly solution for their energy needs. One common characteristic of this group may be that they would have already taken measures to reduce overall energy consumption. That puts them at an advantage when shifting to solar energy, as they know their optimum energy use and can invest accordingly. If you and your family belong in here, you may need only the minimum of preparation.
Investing in solar power to reduce dependency on grid
Some people invest in solar energy because they want an alternate power source. In uncertain times like this, having a single source of energy, and being completely dependent on it, can be a bit unwise, if not downright scary. They may not be looking at solar power systems as their primary provider. They probably want it as just a standby, and the system they invest in may be barely able to cover their actual needs.
Going solar to reduce energy costs
Those who are attracted to solar energy because of its cost effectiveness alone may be a minority. They might want to use solar power as their main source of energy, and expect it to meet all their needs, while being connected to the grid for the benefit of the trade-off.
Before they shift to solar power systems, it is essential that their actual energy requirement be calculated. Otherwise, a mismatch between the investment and the return on that investment may become a major concern later. Unless other measures to cut energy consumption drastically are not adopted simultaneously, their initial investment on a system equipped to meet all their power needs could be very high. And it might take years to realize the high initial cost by way of reduction in utility bills.
For example, if energy efficient appliances are not used along with solar power, your initial investment going solar could be unaffordable. By investing in changing power hungry appliances to more economical alternatives will reduce your initial outlay in going solar. It is cheaper to reduce power usage by using more efficient power appliances than to try and store sufficient power to run them. To store extra energy requires more PV panels, bigger battery chargers, bigger battery capacity and bigger inverters which often then makes a solar system uneconomical.
So, what steps can you take to economize the energy use of your home, thus reducing the upfront investment required to go solar?
Changes to your house in general
Replace all lights with the LED alternative, inside your house and outside. LED lights do cost more than incandescent bulbs but the lifespan of good quality LED’s could be as much as 50 000 hours compared to 1000 hours. Not only would you save on power required to get the same amount of light (60W = 4W LED) you will also be spending far less time replacing globes around the house when the old style bulbs pop at generally inconvenient times.
IF you leave a room, turn off the lights, don’t leave a light on in a room that you are not using. You can install motion detector lights in corridors as you only need the passage illuminated when you are passing through. Replacing incandescent lights with LED has a payoff of typically less than 12 months and reduces your houses light power consumption by 90%.
Make sure your house is well insulated. In roof insulation can be achieved at very little expense. With proper insulation you will need to use heaters and air conditioners far less. Make sure your windows and doors have little to no gaps when shut, reducing drafts. If you have the luxury of having a fireplace in your home, start using it, if not you can install a free standing wood burning fireplace, this would help to keep your house warm without using any electricity, not only do they look amazing in your home they are very effective.
Wood is the most efficient form of heat generation. If you have to use a heater in other rooms that don’t have a fireplace, a gas heater is a cost effective alternative to one that utilises oil or an energy hungry element. If you plan to install a new Air-con, make sure you choose an inverter type as they are far less power hungry as they ramp the compressor up slowly to avoid spikes and surges of energy usage.
For a small household a gas geyser works well for all your water heating needs. A household of 2-3 people could get by utilising a 16 or 20 litre gas geyser for all water heating needs. For larger households with multiple geysers an option would be to retro fit your current geyser to utilise a flat plate collector, negating the use of the built in element during sunlight hours.
Otherwise you can replace your current geyser with a full solar geyser or heat pump. Closely coupled heat pumps and retrofitted geysers with insulated pipes and geysers work much more efficiently than a heat pump that is a long way from a retrofitted geyser due to the heat losses as the water transfers between the 2 units.
If you opt to keep your water heating as is there are ways of making your element geyser more efficient. Wrap all the in-roof and outside pipes with insulation and wrap the geyser with a geyser blanket, these steps will reduce the amount of time the element is activated and heat dissipation is reduced.
Electric geysers can typically consume about 40% of your power. Changing to solar geysers, hybrid solar geysers with gas supplementation, hybrid solar geysers with small electric elements and heat pumps can save a huge amount of power.
Formula for calculating kwh to heat water:
Volume in litres x 4 x temperature rise in degrees centigrade / 3412
Let’s assume we need to heat 200l of water from 20 degrees to 60 degrees:
e.g. 200l x 4 x 40 /3412 = 9.4kwh
Using a 1kw element will heat the water in 9.4 hours and using a 3kw element will take 3.1 hours.
Heat pumps are 2 to 3 times more efficient than electric element geysers, which is a huge saving in power consumption. It is very important to have a heat pump that combines the tank and compressor in the same unit or to have the tank and compressor coupled as closely as possible with the pipes and tank insulated especially if retro-fitting a heat pump. If a heat pump is installed too far from the tank then the heat loss in the pipes to and from the tank can be so significant that it defeats the purpose of installing a heat pump.
Electric geysers typically cost about R6,000 and can consume about R3,500 to R,5000 per annum and heat pumps (compressor and heat pump combined in one unit) typically cost about R20,000 and consume about R1,500 of power with a saving of about R3,500 per annum meaning it pays for itself in about 6 to 8 years.
Solar water heating with assisted water heating with a small element will be about 10 times more efficient that an electric geyser. Solar water heating units typically cost about R10,000 and will pay for itself within 2 to 3 years. Solar water heating with assisted water heating using gas will cost about R18,000 and will pay for itself in about 4 to 6 years excluding the cost of gas.
These figures do not include how much you would save due to the reduction of the size of the solar system required.
Change electric stove and oven to gas
Install an inline gas geyser
Inline gas geysers can be used to supply hot water for washing up
Change your dishwasher to one with a hot water inlet
Boil water with a whistling kettle on a gas burner
Use microwaves sparingly
Toast can be made with the gas grill in the oven or using a gas toast rack placed on a gas burner
Use energy efficient fridges
and freezers, the best would be an A++ energy efficient unit
The trick is to replace as many appliances that utilise elements as possible
Lounge/ Dining room Options
As above – Fireplace and LEDs. Certain new LED TV’s use very little power. Make sure you look at the energy rating when purchasing a new television set.
Good quality hair straighteners don’t use a lot of power. GHD’s element requires less than 100 watts depending on size.
Instead of electric blankets, during winter use winter sheets and duvet covers.
Hairdryers are seen as an essential item, not easy to replace with an alternative. They just need to be used sparingly.
A gas heater would also be very effective in bedrooms.
Patio's and Garden Options
Replace your outside lights with LED’s.
Pool pumps will use about 10kwh or more per day in summer. There are options to change your pool pump to be powered directly by its own solar system, they are however fairly expensive as they use 3 phase motors. In winter it is not necessary to have you pump on for more than 3 hours a day. You can heat you pool with a well-designed set of flat plate collectors.
Use petrol mowers, edge-trimmers and brush cutters.