Self-consumption the key to Solar PV efficiency
With two power retailers recently announcing reductions in solar power buy-back rates some have questioned how this will affect return on investment for the solar energy consumer. Have the benefits of installing a solar PV system been eroded? No, we don’t believe so!
Let’s apply some logic to the situation. If we reduce the transfer of energy between the home solar system and the grid, we reduce our vulnerability to electricity buy-back rates set by energy retailers. Enter the self-consumption model…
What is self-consumption?
Self-consumption is the consumption of PV energy which takes place directly at source – either immediately or delayed through use of storage systems.
Self-consumption is possible through use of:
- Appropriate unit size – the chosen unit should suit each consumption situation
- Change in consumption behaviour – consuming energy as it is generated
- Intelligent energy management through use of smart technologies
- Battery storage systems to store unused solar energy for delayed consumption
Appropriate unit size
When deciding on solar system sizing and the type of panel system needed we take into consideration your typical usage by reviewing recent electricity bills, the number of occupants in your household and consumption patterns.
The proper sizing and the correct configuration of the individual parts the solar system (load, solar yield and storage) are crucial for the cost-efficient operation. It is important not to oversize the storage system as the investment costs would out-weigh the economic benefits.
Self-consumption can be increased by up to ten percent by changing consumption behaviour: only using major electrical appliances during hours when most energy is generated.
The number of appliances that can be switched on at the same time is of course limited by the current power of the PV system – switching on too many appliances will result in “wasted” potential for self-consumption.
Major electrical appliances should therefore be started successively rather than simultaneously. This may be achieved manually or through use of timing devices or delay settings that exist on many appliances, such as dishwashers and washing machines.
Intelligent energy management
New technologies, such as the Power Reducer from Elios4You, enable self-consumption by monitoring your PV export. When it sees that you are exporting your free energy it redirects it to your hot water tank or other heating source, ensuring that no additional power is ever imported to supply the hot water tank. The Power Reducer can even be controlled remotely through a smart phone app.
Battery Storage Systems
In a recent blog we discussed the benefits of reducing your dependence on the grid by use of a battery storage system or battery bank.
In a conventional grid-tied solar system, excess power is fed back into the grid earning you a credit on your power bill. As we have seen, the amount paid for electricity exported to the grid may be well below the price you pay when you buy electricity. So you may create power and sell it to the electricity retailer, only to buy back in the evening at a higher rate.
Battery storage allows solar panels to continue powering your world at night or when there is insufficient sun – without the need for importation of energy from the grid. The result is continuous solar power under any conditions.
For more information on self-consumption and for a free quote phone Murray on 0800 277 548 or email us.