Saving millions

It employs five acres of photovoltaic solar panels to generate one megawatt (MW) of electricity to power its 125 acres of tomato-growing greenhouses.

The company captures and reuses rainwater and water run-off using a four-acre reservoir equipped with filtration technology, while computer-monitored drip irrigation ensures that water and fertilisers are used as efficiently as possible in the production of its hydroponically grown tomatoes. Any excess water is also treated and recycled.

The company estimates that this method of production uses about a sixth of the water and one 10th of the land typically needed to produce the same amount of product via traditional agricultural practices.

But "clean tech" costs have fallen dramatically. For example, installing photovoltaic solar panels costs half what it did three years ago, while improvements in energy-efficient lighting mean businesses can now save millions on their electricity bills.

Light Emitting Diode (LED) technology has been around since the 1960s, but it has advanced so far that the latest units now use less than half the wattage of the high-pressure sodium and mercury vapour bulbs traditionally used in industrial locations, while also providing brighter illumination and lasting for up to 10 years.

Dialight, a British company that specialises in LED lighting for large industry and public sector clients around the world, reckons upgrading from old-school to clean tech lighting can save businesses 50% on their lighting electricity costs and recoup the capital outlay within three years.

Geoff Smyth, head of technology and delivery for the Carbon Trust, agrees, saying: "Lighting accounts for 20% to 50% of total energy consumed in commercial buildings, and a lot of the time the lights don't even need to be on.

"With these breakthroughs in LED and lighting management technology, businesses can achieve energy savings of 70% to 80% and see a payback on their investment within two or three years."

For example, one small hotel upgrading 80 lights to LEDs spent 22,000 on the project, says Smyth, but is now achieving annual savings of 6,600 on its energy bill.

Ron Pernick, managing director of Clean Edge, a US-based clean tech research and advisory company, says: "Innovations in visualising energy efficiency, paired with big data, are already having a significant impact on energy usage. Efficiency continues to be the low-hanging fruit for most companies and governments."

For example, C3 Energy, a "big data" analytics specialist, provides software and monitoring systems that can show large and small businesses how much energy they are using and on what processes, then compare these with buildings and businesses in the same area.

As the software builds up a detailed profile of the business, it can then suggest ways energy consumption can be reduced, such as by upgrading equipment

Similarly, Wireless Energy Management Systems (WEMS), whose clients include Marks & Spencer, BT and Boots, provide a range of wireless sensors and controllers that can monitor and adjust a building's entire energy usage, reducing lighting and temperature levels if it is bright and warm outside, for example.