The terms CleanTech, GreenTech and EcoTech cover a wide-ranging spectrum and embrace many different industries. The clean, green and/or renewable technologies – the number of names in use is even greater than the range of applications – field includes all the industries working to foster sustainable development. This includes waste reductionrecycling and biodegradability, improving the way we consume energy  (consuming less and more efficiently), cutting CO2 emissions and reducing our carbon footprint, air purification, improving water quality and using less pollutant materials – to name but a few objectives. All these technologies have been developed with a view to caring for the environment and avoiding depletion of natural resources. In short, CleanTech is now moving into all kinds of areas: ConstrucTech (more environmentally-friendly town planning), AgTech (sustainable agriculture), transport (pollution-free mobility), energy, and so on. Taking its widest definition, Texas-based market research firm Plunkett Research calculates that the CleanTech sector already accounts for over $3.5 trillion, i.e. around 5% of global GDP.


The signing of the Paris Climate Agreement – the first comprehensive global agreement on climate action in history – following the Conference of the Parties (COP21) to the United Nations Framework Convention on Climate Change (UNFCCC) in 2015 brought environmental issues back into the spotlight and today there is widespread public concern about depletion of natural resources and global warming. And now that the US federal government is pulling out of the Agreement, individual state authorities have started to go ahead with independent action. Hawaii was the first to align with the international consensus, passing a law expanding 'strategies and mechanisms to reduce greenhouse gas emissions statewide in alignment with the principles and goals adopted in the Paris Agreement'. Meanwhile California, which has for several years been leading the way on climate-related action and is spearheading resistance to the policies of the Trump administration, is the major player in clean technologies. In September the state is due to host a Climate Action Summit in San Francisco.

Ambitious, ground-breaking state legislation 

California has already passed a number of laws and regulations designed to help slow the effects of climate change. In the medium term, the aim is to reduce emissions of greenhouse gases (GHGs) so that by 2020 they will be back to the same level as in 1990 and then, going forward, to slash them by 40% of the 1990 baseline by 2030. In California buildings are the second-largest source of GHG emissions, but the State has nevertheless saved over $56 billion on electricity and natural gas expenditure since the adoption of the Californian energy code – the 'Building Energy Efficiency Standards' – in 1978. Eight years later, the Clean Air Act called for limits on emissions of CO2 and toxic particles from cars. Air quality in California is actually still only average (in fact the state has the worst air quality in the entire country) but an increasing number of startups are now developing and marketing technological solutions to improve the situation. The standards adopted in California in1970 are now in force throughout the United States.

Electric power production in California should be 60% from clean energy sources by 2030, and 100% by 2045

California intends to have half its electricity production generated from clean energy sources by 2030. This target was set only two years ago, but could be met by 2020 – i.e. ten years ahead of schedule – according to the California Public Utilities Commission. Last summer a new, more ambitious, target was set: electric power production in California should be 60% from clean energy sources in 2030, and 100% by 2045. Hawaii is the only other State to have set the same long-term goal.

Silicon Valley: innovation at the service of the environment

California is also quite a laboratory for transport, and is planning to make electric vehicles the norm. At the end of 2016, close to half of all zero-emission vehicles bought in the United States were sold in California. In the first quarter of 2017 they accounted for 5% of the state’s total car sales. This year a number of automobile manufacturers have committed to going fully electric. First there is Swedish firm Volvo, which has stated that from 2019 on it will manufacture only vehicles that are equipped with an electric motor. Then there is the US indigenous giant General Motors, which has announced that it will transform the whole of its vehicle offering. The company says it will be introducing two new electric car models over the next eighteen months and launching at least twenty, including these, by 2023.

However, the auto giants are not the only firms innovating in the field of clean technology. Universities are also pulling their weight when it comes to research into environmental engineering for transport, with BerkeleyStanford and the California Institute of Technology (Caltech) each having a department dedicated to this field.

Meanwhile the Los Angeles CleanTech Incubator (LACI), is among the largest California CleanTech incubators. Since it was set up in 2011, it has coached 67 firms, helping to raise $135 million, create 1,500 jobs and over $335 million in economic value. It has recently acquired CleanTech Open, an incubator which focuses more on companies at the very first (seed) stage of development – deciding on a business model, raising funds, and so on. LACI says that its mission is to accelerate the commercialisation of clean technology and job creation in the Los Angeles region. The incubator helps companies with their marketing, initial production and securing investment. Together with the counties of Santa Barbara, Ventura, Los Angeles and Orange, LACI has launched the Energize California network – an 'energy innovation hub' which aims to mobilise the region's ecosystem so as to identify and support entrepreneurs in this domain and accelerate the deployment of clean technologies.

Regard d'expert

Amanda Sabicer

of Energize California

  California has passed revolutionary climate legislation which has been imitated by national and sub-national governments worldwide.

Amanda Sabicer, Vice-President of Energize California, reckons that artificial intelligence, machine learning and energy storage technologies are contributing hugely to the boom in CleanTech. She points out that "in the field of transport, spectacular progress is being made on ‘last mile’ solutions, optimising traffic flows, ride-sharing, autonomous vehicles, electrification of transport and goods transportation." She underlines that "California has passed revolutionary climate legislation which has been imitated by national and sub-national governments worldwide,” and the state "has proved that it's possible to maintain economic growth while at the same time reducing carbon emissions. California is leading the United States in growing the number of 'green' jobs, rolling out solar power and increasing electrified transportation." In the California Green Innovation Index, published by San Francisco-based organisation Next 10, the state authorities make the observation that since climate change legislation was passed in 2006, GDP per person has increased by close to $5,000, and employment growth is 27% higher than the United States average. 

Solar becoming a religion

Ernesto Sanchez - Credits: Ernesto Sanchez
Sarah Swenty/USFWS - Credits: Sarah Swenty/USFWS

Florida is known as the Sunshine State, but California could well lay claim to that title. The state generates so much solar power that it pays neighbouring Arizona to take its surplus production. All in all, California sells its surplus power on to no fewer than seven other states. The surplus power issue is however now being addressed by Silicon Valley giants: at the beginning of this year Tesla and Southern California Edison unveiled at Mira Loma (east of Los Angeles) the world’s largest battery storage facility (now facing competition from a second Tesla plant in Australia). The installation – designed to absorb excess power from the grid during the day and reinject it into the system in the evening, when less solar electricity is available but demand surges – means that enough energy can be stored to power 15,000 households for four hours. It certainly looks as if energy storage has a bright future and the State of California has the highest number of jobs in the sector. The same goes for solar power, which country-wide provides employment to – according to The Solar Foundation – over 250,000 people, a figure that has risen by at least 20% over the last four years. Between 2010 and 2015, solar energy production increased by over 1,738% and in 2016 the industry contributed $84 billion to US GDP.




Kern and Los Angeles counties host Solar Star, the world's second largest solar farm. The electricity generated by its 1.7 million photovoltaic panels is sufficient to power around 255,000 Californian households, at the same time avoiding annual CO2 emissions equivalent to those from 106,000 cars on the road. Moreover, there are two other large solar farms, Desert Sunlight and Topaz Solar,  in the State. Meanwhile last year San Francisco unanimously passed local legislation stipulating that the roofs of all new buildings of less than ten storeys should be equipped with solar panels. Throughout the State, residents receive cash-back incentives for doing the same thing in their own homes.

The surge in solar power is now providing inspiration to a number of companies: local startup Soliculture builds greenhouses installed with LUMO technology, which combines photovoltaic technology for electricity generation with luminescent red light to help optimise plant growth.

Riding the wind

In addition, California accounts for 4% of all US jobs in the wind turbine sector – an industry which has seen over $12 billion worth of investment at state level and is expected to generate more than $85 billion in revenue across the United States as a whole by 2020. The American Wind Energy Association  (AWEA) ranks California second in the country for the number of turbines in use and fourth in terms of installed capacity. Alta Wind, one of around a hundred wind turbine projects in California, is the largest wind farm in the country and the second largest worldwide.

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While the US east coast has the lion’s share offshore wind turbine projects – because the Pacific Ocean is too deep to anchor the turbines – California might nevertheless change all that with a wind farm comprising a hundred floating offshore wind systems (FOWS) that is being developed by Trident Winds off the Californian coast, with a grid connection in Morro Bay in San Luis Obispo county. Commercial exploitation is scheduled to begin in 2025, with around a hundred FOWS moored to the ocean floor with cables. This is a ‘first’ in a state where the most unique wind farm is an installation at Stanford University that uses vertical axis wind turbines. In a report commissioned by the Department of Energy, a team of researchers and engineers say they see wind-power as a promising source of renewable-sourced electricity across the entire United States and that it could make up 35% of US electricity production by 2050, thus avoiding the emission of 12.3 gigatons of GHGs and enabling some 980 billion litres of water to be saved.

Water, heat, and biomass completes the range of renewable energies

North of San Francisco, the Mayacamas mountains are home to the world’s largest geothermal field – the Geysers. These are a huge source of energy, and eighteen geothermal power plants are already channelling steam from over 350 wells to produce sufficient electricity to power 900,000 homes in Sonoma, Mendocino, Lake, Marin and Napa counties. In fact the Geysers deliver 20% of all the green energy produced in California. Mammoth, a smaller geothermal complex in the Sierra Nevada, runs three geothermal power plants, which power 22,000 homes.

Last but not least in the green energy spectrum, in October the California Energy Commission approved plans for a biomass system in Shasta county and allocated a $1.5 million grant to Berkeley-based All Power Labs, which is in charge of processing thousands of tons of forestry waste derived from California's unprecedented tree die-off. Meanwhile, California is not working alone. The state authorities intend to inspire the rest of the country and also regularly meet up with high-level politicians from other countries. Last April, at a meeting in San Francisco, Canada and Mexico signed up to the Under2 Coalition, a global pact whose purpose is to help reduce greenhouse gases. Then in June, a partnership was signed with California's 'twinned' state in China, Jiangsu Province, whose terms call for efforts to combat global warming.

By Marie-Eléonore Noiré