14 June 2016
Storage Technology and Intelligent Systems Form Next Green Wave
With government subsidies on the decline across the UK, environmental businesses are increasingly looking to make a clear commercial case for the savings and other decided advantages inherent in the new generation of green tech.
Overall, the sustainable building professionals at London's Ecobuild expo were resolutely optimistic about the future, despite the cutbacks to UK government subsidies for green energy and relatively low energy prices. As it matures, the industry is looking to smarter, more efficient systems to stay competitive, buoyed by falling costs and higher levels of technology transfer from kindred industries. While some exhibitors saw the greatest gains to be had from improving technology, others believed that smarter collaboration and local networks remained the keys to unlocking the potential of the renewables sector.
Ecobuild is the leading UK exhibition and conference for the construction and energy markets. These markets are heavily influenced by government policies and energy prices, with last year's event dominated by politicians, all mindful of the looming May 2015 UK election.
This year, the new government is committed to cutting public spending. Green incentives have either been cancelled or are subject to review, energy prices remain low and widespread uncertainty has discouraged investment. Despite this, the exhibitors and speakers at the event made a robust business case for adopting green solutions – with or without government incentives.
The UK photovoltaic (PV) panel market was once heavily reliant on generous government Feed-in Tariff (FIT) payments, which allowed surplus electricity to be sold into the National Grid. In a residential setting this is very important, with most power generated during the day when houses tend to be unoccupied.
Although the prices of PV installations have dropped, FIT payments have also fallen making the payback period far longer – unless, of course, a greater percentage of the power can be used in the home. Fortunately, the rise in demand for electric-powered vehicles has stimulated the manufacture of smaller, lighter, more efficient storage batteries, inevitably resulting in a price drop.
This year, the stand of almost every PV technology exhibitor included a home storage unit. Users can now consume more home-generated electricity and even store electricity 'imported' from the grid at low night time tariffs. The units can also provide back-up power during outages.
A good example of this was the Powerwall, available courtesy of Tesla, a Californian electric vehicle maker. The system boasts a 6.4kWh capacity, providing 3.3kW power and offering 92.5% round trip DC efficiency. The device is available through several PV suppliers, including Cheshire-based Greentech.
According to Rob Johansen, a Sales Executive with Greentech, the device is relatively straightforward and involves minimal disruption. He did, however, concede that it required a separate inverter for DC to AC conversion.
Another approach to battery storage was BSUK's Energy Storage System, a range of free-standing units incorporating both batteries and inverters. Power outputs vary from 1,500W to 3,000, while capacities are in the 3.2kWh to 8kWh range. Emphasising the flexibility of the system, Scott Kirk, a Director of the company, said: "The mobility of the units means they can also be used as temporary power sources for outdoor leisure activities".
Travelling from slightly further afield, Israel's SolarEdge was in London to promote its optimised inverter, a system that manages and monitors PV production and that has now been integrated with the Tesla Powerwall. Germany's SMA, meanwhile, was exhibiting an integrated system for combining PV and storage with intelligent control and internet access. Using a 2kWh storage battery, it utilises the intelligent control of higher power equipment (such as washers and driers) to increase the efficiency of PV electricity use.
Looking to the future, Ray Noble, a Photovoltaic Specialist with the Renewable Energy Association, said he expected battery storage to follow the development pattern of PV panels. This would see the initial high costs and low efficiencies rapidly improve as the size of the market grew.
He sees the renewable energy market as likely to be transformed by enhanced storage capabilities, overcoming the intermittency problems of both wind and PV. Storage upgrades would then be a source of new business from existing PV users, while also helping to promote market growth in terms of new installations.
The prospects for commercial installations, despite the setback caused by the reductions in FIT tariffs, are also now improving. This has been down to falling installation costs which have helped to balance the financial returns, with a number of companies also adopting green policies as part of their branding.
Keen to tackle the issue of making renewables work in practice in a post-subsidy world was Dan Grandage, Head of Responsible Property Investment at Aberdeen Asset Management. Leading a seminar devoted to the subject, he outlined his belief that complying with the government requirements for receiving FIT payments had often proved restrictive and had resulted in delays. Working without subsidies, he argued, might now allow for greater flexibility and speed, increasing the overall size of the market and, ultimately, helping capital costs to fall.
While most PV installations require access to large areas of roof and a consumer to purchase the power generated, an alternative approach was on offer from Cambridge-based Polysolar. Its Building Integrated Photovoltaics (BIPV) and PV glazing technology sees PV integrated into the building itself. This process is said to be only marginally more expensive than the use of conventional construction materials, while also providing a means of raising the building's score in BREEAM and LEED sustainably certification schemes.
A further interesting potential market was outlined by Simon Daniel, Chief Executive and Founder of London's Moxia Technology. He advocated linking homes that have PV and storage installations into a 'smart local grid'. This is in line with two current initiatives – Energy Resource in Communities (ERIC) and (Meter Attached Storage) Energy Management System (MASLOW).
One community energy project in Oxford has already seen the installation of 60kWh of storage alongside a new solar PV system. To date, the project has demonstrated the practicality of solar-self-consumption and the benefits of sharing storage resources across a community under a new and innovative tariff. Properly implemented, the system can help the utility grid meet peaks in power demand, while remaining under central control via the internet.
Power from other sources can also be incorporated into local grids with Darren Bolton, a Commercial Energy Consultant at Scotland's VG Energy, keen to explain how the biomass CHP (combined heat and power) system his company was exhibiting could be used to provide both heat and electricity to an industrial plant or a local community using wood chip feedstock. Wind generators and large battery storage units could also be incorporated into local grids, he said, and were particularly suited for use by isolated communities.
While renewable energy clearly has a role to play in reducing carbon emissions, a number of exhibitors had on offer several other energy-saving solutions, including one of the most tried and trusted of them all – insulation. Leicester's Radmat and Ireland's Kingspan jointly presented a vacuum-based product, suitable for use on inverted roofs, terraces and balconies. The particular form of insulation sits on top of a waterproof layer and can be covered with gravel, paving or green roof, making it suitable for both new builds and retrofits.
One of the biggest success stories in terms of overall energy saving is, of course, LED lighting. Understandably, then, such systems were widely in evidence this year. Hong Kong-based Nanogrid, for instance, had on offer its Nanoleaf range of lightbulbs.
Explaining the approach taken with its printed circuit based product, Jonathan Tam, Nanogrid's Business Development Manager, said: "As our product is approximately the same size and shape as a traditional bulb, it is simple to substitute it. Our use of the printed circuit approach, however, also allows for further sophistication in the future. This could see such functions as occupant sensing, home security utilisation and programmability all on offer".
With natural lighting levels and air conditioning becoming more important in the UK, a number of companies were keen to capitalise on the commercial opportunities in this sector. One innovation that seemed to be finding popularity this year was the use of air source heat pumps in reverse mode as an alternative to conventional air conditioning.
With this in mind, ground source heat pumps and earth tubes can be incorporated into air conditioning, with air source heat pumps said to be easy to install in both new and existing buildings. Highlighting the benefits here, Southampton based Freedom Heat Pumps of Southampton had on offer its Ecoforest ground source heat pump system. As an alternative, Shenzhen's Power World Machinery Equipment was showing its proprietary range of heat pumps, including enhanced vapour injection (EVI) models that can work at temperatures as low as -25°C.
When it comes to building overheating, one of the common source of problems is the large glazed areas that are now common in many commercial premises. With this issue in mind, Swansea's Umbra Shading was keen to promote its Idealite system. This intelligently manages natural lighting in order to optimise illumination, reduce sunlight overheating and minimise glazing heat loss.
While Ecobuild showcases many of the large companies and organisations in the building and energy community, it is also a launching pad for smaller companies. Two such notable additions to this year's roster were Buxton's Showerpowerbooster and Brighton-based Waterblade. In the case of the former, Director, Susan Wright, was on hand to demonstrate its simple 12-volt power booster for increasing in-home water pressure. Nigel Bamford, Waterblade's founder, meanwhile, was in London to promote his water-saving device that can be fitted to hand washing taps and can turn a trickle of water into a 'blade', suitable for efficiently washing your hands while also reducing water and energy consumption. Indeed, so impressed were attendees that this product took the overall Innovation Award at this year's show.
Ecobuild was held at London's ExCel Centre from 8-10 March. The event's exhibition space attracted more than 800 building and energy brands.
Glenville Holmes, Special Correspondent, London