Knowledge : Net Metering
Counting the benefits of net metering , grid parity and electric vehicles
Ayrshire based Beyond Innovation ltd have been at the heart of designing renewable energy products for over 16 years now , and Director Dougie Blair ( left ) takes a fresh look at what ’ s holding back the Solar PV markets in the UK . Since the virtual demise of FITs in January this year , the PV industry seems to have fallen asleep at the wheel . It ’ s widely recognised , through bitter experience in many cases , that PV offers one of the most stable and predictable sources of power generation in the UK . Despite this , it ’ s now widely assumed by the public that PV has “ had its day ” and is no longer a good investment , since the returns are not as good as they once were . The reality is PV could be re-invigorated by the introduction of what is known as Net Metering . The UK Government has yet to make Net Metering commonplace , by legislating that energy companies must offer it to those customers who would benefit , as is the case in the United States and many EU Countries , where PV has created a wealth of opportunities for both installers and consumers alike , as a direct result of its introduction .
Net Metering involves the counting of any exported units ( or kWh ) of unused power from a PV system ( or other forms of renewable power generation ), allowing that power to be “ banked ” on the grid for later use , either at night or in the winter . In practical terms , a 4kWp PV system that operates in a domestic setting , where the owner leaves for work each day , would see the bulk of the power generated during the day from his / her PV system being spilled onto the national grid . In the evening , as the household ’ s demand increases , and the production from the PV system ceases , the homeowner currently needs to buy back the power which spilled onto the grid earlier in the day , and pay the full retail price for it , despite the fact that it was their own power which spilled onto the grid earlier in the day . With Net Metering , the spilled units of power can be effectively “ bought back ” free of charge in the evening , or at a later date , thus levelling out the use of the PV power , irrespective of when it was generated . PV power is typically spilled onto the grid during the day when big business and industry requires it most , and is bought back in the evening when the grid is “ backed off ” through lack of demand . PV is unique in its power generation in this respect , in that it produces excess power when it ’ s required most by the
22 | www . renewableenergyinstaller . co . uk grid . Allowing domestic customers to buy back their spilled power in the evening is an ideal use for that banked power . Net Metering would achieve this . Currently , most domestic PV installations provide as little as 15 per cent direct use of the power generated by the system , while with Net Metering , that figure would rise to 100 per cent . The importance of being able to use 100 per cent of the power
Left : With Net Metering the spilled units of power can be effectively “ bought back ” free of charge in the evening , or at a later date , thus levelling out the use of the PV power , irrespective of when it was generated .
generated by investing in PV couldn ’ t be more critical at this time . The reasons for this are not complex , but a UK Government which doesn ’ t recognise and implement the introduction of Net Metering is spoiling a glaringly obvious opportunity . In the absence of Net Metering , the solar PV industry is now looking at “ self consumption ” battery storage systems , which create a virtual Net Metering system