3rd Generation Technology refers to production of biofuels from algae and aquatic biomass. Algae are the plants that range from microalgae to large seaweeds. Algae are an alternative source of biofuel because it fares better than the other natural sources for producing biofuels in greenhouse gas emissions and resources needed for fuel manufacturing except energy. There are different varieties of algae such as macroalgae and microalgae.

Microalgae are very small in size in contrast with macroalgae. Microalgae can occur in highly diverse environments and nurture under strongly fluctuating environmental conditions. Microalgae biomass is harvested from natural waters as well as cultures in artificial ponds, photobioreactors (PBRs) or developed through fermentation and then detached and sprays or sun dehydrated. Some algae are grown in the dark using sugar or starch also.

Seaweeds are of different variety such as green, brown and red and each of them has their own speciality for example brown seaweeds are dominating the harvest twice the volume of red seaweeds and on the other hand green seaweeds are less valued henceforth are not harvested in substantial quantities. As per The Food and Agriculture Organization 2014 estimations, globally aquatic plants dominating seaweed; 26 MMT (wet weight) were produced in 2013.There has been an upsurge of 129% in seaweeds harvested from the past 13 years.

As per the European Biofuels Technology Platforms, algae and aquatic biomass has the potential to produce a unique range of biofuels. Algae and aquatic biomass supposed to have lower area necessities compared to crops such as corn, rape seed or switch grass. As per the recent trends, advanced 3rd generation biofuels can reduce 120% efficiently the greenhouse gas (GHG) emissions as compared to diesel extracted from soy oil and other natural sources.

Recently, U.S. Department of Energy announced six projects that will be receive up to $18 m in funding to develop valuable bio products and biofuels from algae and also to lessen the value of algae-based biofuels to less than $5 per gasoline gallon equivalent (gge) by 2019.In additional to the advancement in technology to generate biofuels some companies are also engrossed in leveraging cooperative agreements to achieve substantial private investments, form strategic partnerships and validate the pre-commercial production levels of algal biofuels.
 
Below are the few organisations those who are taking initiatives for the developing biofuels through algae and aquatic biomass.

• Algenol Company started operating its pilot-scale integrated biorefinery, which establishes the commercial viability of its two-step fuel production technology. The company has an algae strain that can produce ethanol directly, and the system can then transform residual biomass into hydrocarbon fuels such as biodiesel, gasoline, and jet fuel.
• Sapphire Energy is a manufacturer of algae-based “green crude” oil. The company with recent receiver of DOE funding, entered into contract with major oil and gas companies i.e. Phillips 66 and Tesoro. All the three companies have their defined roles like Phillips 66, an integrated energy manufacturing and logistics company, partnered to test and upgrade Sapphire’s green crude to on-spec diesel. On the other hand, Tesoro, an independent refiner and marketer of petroleum products, entered into a commercial purchase agreement for its green crude oil. Sapphire is anticipated to establish Nation’s first algae oil on a commercial scale by 2015.
• The Arizona State University-led Algae Testbed Public-Private Partnership (ATP3) and the University of Arizona Regional Algae Feedstock Testbed (RAFT) partnership working on the research and development of algae-based technologies.  Both partnerships manage algal biofuel research and development facilities across the U.S. and serve as learning environments for the next generation of scientists.

The above chart depicts rise in the consumption of biodiesel in U.S. by 4% in 2015 compared with 2014 and the production decreased by 1.3% compared with preceding year in 2015. From the above facts, it can be drawn that biofuels will be the forthcoming trend for diminishing GHG emission from the world.

Thus, 3rd generation technology has significant potential to replace existing technology in the market and can also drive biofuels market in near future.