Solar Microinverters typciall sell for 75-90c/watt which means that if all the solar installations in the world at around 18 GW were done using microinverters,then the size of the addressable market would be $12.5-16 billion,however a lot of the installations are larger than 1 MW in which micro inverters are not used.Also micro inverters are mainly sold in the US and Canada so the total size of the addressable market becomes more like 500 MW which is around $$375-450 million dollars.Enphase Energy the biggest microinverter manufacturer has sold around 500,000 prouducts which implies total lifetime revenues of around $40 million.According to IMS Research around 1 GW of microinverters would be installed in 2013 and the market size would be around $700 million.I think the market size will be greater given that other geographies have not been penetrated,the residential solar market is growing faster and more companies will lead to a bigger market

With most of the low hanging fruit of polysilicon costs already gone,the industry has to focus on efficiency to cut down on costs.Selective emitters,microinverters,DC-DC optimization and other technologies are already finding takers.A Number of microinverter companies like Tigo,Enphase Energy etc are tying up with global heavyweights like Suntech and Sunpower to increase their penetration and cut costs.National Semiconductor has also tied up with Suntech to integrate its products with Suntech Modules to improve efficiency and reliability.The Balance of Systems costs for Solar Panels and their Performance are not usually paid a lot of attention.But with every cent now making a big difference,these technology could make or break a company in this commoditizing industry.While the value addition and costs of these new products are still subject to market acceptance,its a major change for the industry.This is the next phase in the evolution of the solar energy industry as it looks to additional ways to cut costs and bring solar energy to grid parity.Look for M&A in this space as well since the industry is fragmented with a host of VC backed startups.