With cultivation so closely intertwined with the Internet and with the advent of crop and climate sensors, big data is becoming available to the greenhouse horticulture sector. Big data consists of huge collections of information that growers can use to optimise operational aspects such as crop growth and energy consumption. A consortium of companies and organisations is working on the calculation models and algorithms that should make a comprehensive management program possible. “Think of it like a satellite navigation system (satnav): the grower enters a target and the program guides them there.”
“Imagine you’re a tomato grower. Wouldn’t it be great if you could manage your yields, quality and harvesting times even more accurately than you do at present. What buttons should you press to achieve that? That’s what we’re working towards,” says Simon van Mourik, Assistant Professor at the Farm Technology Group at Wageningen University & Research in the Netherlands, where he works on intelligent agri-systems based on precision technology and data streams.
Van Mourik has teamed up with energy specialists AgroEnergy to lay the foundation for a joint research project. The university, the energy partner for greenhouse horticulture and a number of companies and organisations were recently awarded funding for this project, which is entitled “Energy saving in greenhouse crop production by flexible management” and goes by the working title “FlexCrop”. The research project will start in a crop of artificially lit tomatoes next summer. The consortium also includes the Dutch growers’ organisation LTO Glaskracht and the companies B-Mex, LetsGrow.com and Delphy.
Developing a management program based on big data is no small matter. A period of four years has therefore been allowed for FlexCrop. There are a lot of requirements to be met. First of all, the program must be able to adjust for temporary fluctuations, just as a satnav recommends an alternative route for the driver if there is congestion ahead. “This dynamic must be built in. So the program must steer dynamically. In terms of climate and energy consumption, for example, that can be done by adjusting the settings hour by hour based on the most recent data,” says van Mourik.
Analyse and interpret
All the relevant cultivation factors must be built in. For example, B-Mex is looking at forecasts from changed settings. Take the CO2 dosage. What happens if the grower increases the concentration of CO2? What would that cost? And what would it deliver in terms of crop growth or extra kilograms of product? Based on the measurements and calculations, the program must be able to recommend the best and most cost-effective CO2 dose for the crop.
Van Mourik: “Next Generation Growing has already taught us that a crop is very flexible. With even more information about this, we can develop an algorithm that optimises the settings accordingly. That calls for models that predict the consequences of a particular action or situation. These models do already exist but they are not yet perfect. The challenge is to analyse and interpret the enormous volume of data in the right way.”
Two PhD students are helping with the research. One is working on knowledge of crop physiology and the other is working on an algorithm that utilises the flexibility of the crop. “In this project, the trick will be to make the best use of all the partners’ expertise,” the Dutch scientist says.
For growers, the datasets on which the management information system is based are invisible. Will they have the courage to trust the advice? Van Mourik thinks so. “Look at the satnav. You don’t know how it works but you still follow the instructions and you do what the screen on the dashboard tells you to. ‘After 300 metres, turn left’ – and you really do turn left after 300 metres. And that gets you where you need to go.”
Intertwined with business aspects
One example of where big data can take us is BiedOptimaal from AgroEnergy. This program calculates the optimum APX bid for the next day based on extensive data sets and prediction models. More than 130 growers are already using it every day. There’s a lot to be got out of the energy market for the grower, AgroEnergy product developer Peter Goudswaard explains. “Energy is an important part of the cost price and energy prices can fluctuate strongly on the APS and the intraday market. With the right APX bid and by adjusting for intraday, you can use the program to make significant savings in energy costs and time.”
At the moment the company is working on a series of additional solutions designed to help growers with everyday issues. There’s no shortage of examples. Goudswaard: “Is it worth switching on the lights or would it be better to leave them switched off? What would it cost you in the first scenario, and what would you save in the second? And what does the crop do when the lights are on or off? What extra yields could you get, and what costs would be involved? The program doesn’t approach the cost factor of energy in isolation and is becoming more and more closely intertwined with many areas of production, climate and day-to-day operational aspects. We are working with a number of partners on this.”
Support for decision-making
Goudswaard’s colleague Bram van Rens is a data scientist at the Delft-based energy specialists: “The yield has to come from cultivation, whereas climate is a cost factor. It takes time if the cultivation manager and the energy manager keep having to meet because the cultivation manager wants to switch on the lights to boost growth and yields while the energy manager wants to feed energy back into the grid because prices are good at that point. Their objectives differ, but cultivation and energy are both factors in the company’s bottom line: they have to go hand-in-hand.”
Big data makes it possible to provide advice that will highlight the optimum, van Rens believes. “With systems that support decision-making we can make things easier for the grower. As sensors and the Internet of Things produce more and more information and data, there is an increasing need for this.”
Less to the daily market, higher mid price
The Dutch company HortiKey is working on other applications based on big data. The company’s latest innovation is the Plantalyzer, which has been developed for tomatoes to begin with.
The autonomous measuring system photographs the colour of the tomatoes on a scale from 1 to 12. The measurements are then used to produce a forecast of the harvest in kilograms two weeks in advance. This is very handy. After all, if the grower knows that in two weeks’ time he will be producing more than he is contracted to deliver to the customer, his sales staff can start looking for alternative outlets. General Manager Andreas Hofland: “Otherwise they have to get rid of the surplus on the daily market, where prices almost always put pressure on their mid price. With this system, you can reduce the normal margin of error in production planning by around ten percent.”
When all is said and done, the measuring system is a sales tool, Hofland says. But it is a little more than that, because it also highlights production differences and can detect colour variations. “If some trusses are ripening differently from the others, this tells the crop manager that there has been a problem there. If he is able to find out exactly what that is, that mistake can be avoided in the future – even if it was only a leaking window. This is a way for inquisitive growers to get their hands on a wealth of new information.” The company mainly specialises in applications for large fruiting vegetable nurseries. That’s a strategic choice, because these nurseries are becoming larger and larger the world over, and yet it is becoming harder to find good crop managers and the risks (in other words, errors in cultivation or production) still have to be eliminated.
The trick with big data is to recognise patterns in the enormous streams of data and convert them into information that can be applied to the grower’s day-to-day practice. Various parties in the greenhouse horticulture sector are working hard on this. A consortium is developing a management information system based on big data, for example, and one company is focusing on yield forecasts that helps growers manage production and sales even more precisely.
Text and images: Jos Bezemer.
The bi-annual AgroEnergy symposium was held at the Rotterdam STC Building’s Lloyd Hall on 21 January 2016. The key topic of the symposium was: ‘How can tomorrow’s energy be applied to today’s greenhouse?’ Led by Frits Wester, seven speakers from the energy industry presented their vision on this topic. This article will feature the highlights of trendwatcher Adjiedj Bakas’ presentation.
Adjiedj Bakas, the Netherlands’ most prominent trendwatcher, kicked off the symposium with a sharp analysis of what the world will look like in 2025. He predicts two major shifts, which he describes as ‘climate sobriety’ and ‘new aesthetics’. He called 2015 a year of great inventions and predicts rapid changes, in which he addressed the symposium’s topic of how the energy we and the greenhouse horticulture industry will be using in the future will be generated: at the bottom of the sea, among other alternatives. Tidal energy is a promising source of energy, as are small windmills without blades. ‘Energy will be available practically for free in 20 or 30 years.’
Energy from seaweed
According to an idea that dates back to 1920, we are technically able to combat climate change by creating clouds from seawater with specially designed small boats. Japan will be experimenting with a solar energy plant in outer space. We will also be growing seaweed in floating greenhouses that can be moved about as we like. Seaweed could very well become the energy source of the future. ‘What we need most are radical, new ideas,’ he advocated. Co-creation and co-makership are also rapidly emerging trends.
Energy from nuclear waste
However, these aren’t the only interesting innovations today. The first medicines produced from flowers are already available. Coffins are being made from potato peelings, on which a tree can grow beautifully. A more beautiful and sustainable memorial is hardly imaginable. Bioplastics are made from plants, which offers new possibilities for the horticulture industry. We will be generating energy on the façades of buildings. And nuclear energy will experience a comeback, but in an entirely new way. New nuclear power plants will be running on nuclear waste, or thorium. ‘The oil era won’t come to an end due to a lack of oil, but because people will be choosing alternative energy sources.’ Waste will no longer exist; everything will become a resource. Water is already being recycled in the horticulture industry.
‘A lot of money is being put into innovation these days. Bank interest is reaching the zero point. Venture Capital is available everywhere; funding has never been so easy to arrange!’ Opportunities abound for the horticulture industry, according to Bakas, but this will ‘demand a certain spirit’. His advice to horticulturists: ‘Experiment, get off the beaten track. Make your own path! Speak to people outside of your own sector,’ he advised the audience. ‘See what other industries are doing and focus on creative solutions rather than efficiency.’
Text: Mario Bentvelsen. Photo: AgroEnergy.
Now that the rates for the return of electricity have dropped lower than ever before, growers will have to make all possible efforts to achieve a profit on the imbalance market from their CHP. AgroEnergy is launching a new service that will allow growers to place bids directly on the control power market, which will enable them to trade actively through TenneT. This initiative would also allow growers to collectively offer emergency power.
Cogen Nederland, the Dutch association for the promotion of CHP, anticipates that the current capacity generated by CHP units will be reduced by fifty per cent in the next decade to come. With a rate of 3.6 cents per kWh and a peak rate of 4.8 cents for the next three years to come, the energy market is suffering tremendously. The peak price will barely cover the variable costs of a CHP unit. Nevertheless, Arjan van der Spek of Enova is convinced that the fifty per cent referred to above will probably not be achieved, taking into account that half of all growers deploy their CHP units for assimilation lighting for their own crops anyway. CHP is here to stay. With regard to the fifty per cent that would remain unused, growers will have to rely on returning electricity to the grid at the right moment. ‘They will have to actively make use of this option.’ There is, however ray of hope as opportunities on the imbalance market are likely to improve. The increasing number of wind turbines and solar panels has heightened the risk of imbalance problems in the supply of electricity. After all, no electricity will be generated when the sun doesn’t shine or there is no wind.
Power control under contract
‘Based on the by-the-minute forecast price, growers can adjust their CHP production upwards or downwards through the imbalance control platform’, explains Willem Bijlsma of Tenergy Services. ‘This will allow them to benefit from the higher rates arising from a shortage in electricity at a particular point in time. TenneT, however, determines its quarterly rates in retrospect; you can never forecast precisely how much you will earn. This is a drawback in passive participation on the imbalance market. Additionally, this supply option is gradually phasing out because TenneT prefers to regulate the supply of energy through contracts.’
TenneT contracts extra control power capacity for a sufficient supply of energy on the imbalance market. As TenneT concludes these contracts with large energy companies, and not with greenhouse growers (these parties being simply too small), AgroEnergy is developing a service that will let growers offer their CHP as control power capacity. This service will be launched on 1 October 2015. The collective power will than be offered to TenneT by means of a bid, provided that the capacity will amount to at least 5 MW. ‘Every grower can subscribe and decide for himself whether or not to participate’, explains Fieke Rijkers of AgroEnergy. ‘In the event that we are unable to supply the required 5 MW, Eneco will make up for the deficit. The biggest advantage for growers is that they will get the rate that has been fixed at that particular moment.’
Rijkers believes that growers will benefit in terms of security by collectively offering control power capacity rather than responding to the imbalance market without a contract. ‘This will provide growers a realistic alternative to earn some extra money on top of the long-term spark spread and trading on the Amsterdam Power Exchange (APX). As soon as TenneT gives the sign for delivery, participants will have thirty seconds to respond with an upwards or downwards revision. This will require some adjustments with regard to the necessary software.’
Making use of all the available options
Robert Willemsen of Powerhouse – a subsidiary of RWE – is wondering why a grower would allow his CHP unit to contribute to a pool, ‘particularly if a fine applies when you fail to respond in time.’ This is, however, not the case with regard to the product offered by AgroEnergy, taking into account that this concerns voluntarily offered control power capacity instead of a fixed contract with TenneT. His solution: ‘Make sure that you get the most out of your CHP unit and that you are using good software. For an optimum yield you have to make use of all the available options: the imbalance market, the APX and keeping a vigilant eye on the highs and lows: selling when the price is up and buying when the price is down. Not everyone will be able to do this equally well; it requires a lot of time and attention.’
Stijn Schlattman of Energy Matters argues for adequate compensation for flexible power supply to compensate for the fluctuations in the supply of wind and solar energy. ‘It is important that gas-fuelled engines are able to contribute to this. This will improve the case for gas engines and people may even begin to invest in new gas engines. Following on another two meagre years with a weak market and a low spark spread new opportunities are arising fro flexible CPHs. Until then owners of CHP units will simply have to muddle through.’
Contract for emergency power supply
TenneT contracts emergency power supplies to compensate for possible failures at power plants. This counters the considerable imbalance on the electricity grid. Back-up generators or CHP units that would otherwise be on stand-by could be used for this. The power generated by these, which is used once a month on average, must be continually available. Companies can register on an annual basis for a scalable emergency power supply of 350 MW, to be made available within ten minutes. This could be financially worthwhile, says Hendrik Koetsier of Energie365. Energie356 collects flexible power from companies for emergency power supply for TenneT. This flexible power supply is provided by companies with back-up generators. Koetsier has noted interesting opportunities for CHP units in this. However, the power generated by multiple growers would have to be offered collectively, because TenneT applies a 20 MW minimum. This would enable infrequently deployed CHP units to nevertheless bring up some cash. TenneT pays an annual availability compensation of over ten thousand euros per MW, plus a variable compensation for the electricity actually supplied. ‘Supplying emergency power could be interesting particularly in cases where a CHP unit generally doesn’t produce anything normally, while entering the imbalance and control power markets is a more obvious alternative for CHP units that are deployed on a regular basis. Emergency power is a better option for CHP units that are not deployed as frequently.’ The drawback is that the emergency power reserved for TenneT has to be continually available; a grower will neither be able to offer it on the imbalance market or the APX nor make use it for his own crops in peak periods.
Supplying emergency power is not a viable alternative for growers who make use of assimilation lighting, says Remco Wiegmink of NIFE-energieadvies. Chances are high that the emergency power will be demanded from the grower when he needs the electricity for his own crop. Besides this, the power may need to be delivered at times when there is no demand for heat. It is doubtful whether the yield for emergency power contributed by a CHP unit that would otherwise not be producing will be sufficient to cover such fixed cost items as gas power and transport. Growers switching to geothermal heat hardly ever offer the power generated by their CHP units on the imbalance market for this reason alone. Robert Willemsen of Powerhouse even considers participating in pools like this a ‘very dangerous’ option. ‘It is better to participate in the control power or imbalance markets by gearing the sale of your power to the opportunities that come your way.’
CHP yields only minimal returns in the horticulture industry. A new CHP unit is not profitable unless it is used for assimilation lighting for your own crops. Based on variable costs, if you already own a CHP unit selling power to the grid will barely be profitable. According to Schlattman of Energy Matters operating hours for CHP units are dropping as far as approximately 3200 hours a year. Fieke Rijkers of AgroEnergy understands the difficulties faced every day by growers placing a bid on the APX, in terms of calculation effort as well as time. ‘The automated BiedOptimaal system offered by AgroEnergy will take a load off their shoulders.’
Robert Willemsen of Powerhouse: ‘Growers who own a CHP unit that has not been written off yet will have to deploy their CHP unit very carefully in order for it to be profitable. If it does not operate for at least 4,000 to 4,500 hours it will be very difficult indeed to pay back your investment. On top of that, you can optimise short-term returns through the APX and the imbalance market. The price risk is, however, high. In fourteen years’ time I have never seen rates as low as they are now, with 3.6 cents per kWh and a peak of 4.8 cents for the next three years to come. The peak price is just enough to cover the variable costs of the CHP, so this will only be profitable with an old CHP unit. The problem is that you can’t simply shut down a CHP unit when you have taken out a 3,500-hour maintenance contract. In this case, your best bet is to deploy it as frequently as possible, if only to minimise your losses.’
Source: Tuinbouwteksten.nl/Theo Brakeboer. Photo: Mario Bentvelsen.