Using Demand Flexing to Transform Indoor Farms into Renewable Energy Assets

In this project we will demonstrate how coordinating renewable energy availability with energy expenditure enables PACE horticulture facilities to be an asset to the evolving smart energy grid.

The lack of fruit and vegetables on supermarket shelves this spring arose from a multitude of factors, including high energy prices discouraging UK growers from planting protected horticultural crops during winter 2021/22. Lighting, heating, and ventilation each contribute to energy bills for growers but lighting can comprise 70% of these costs in indoor farms and light intensity is immediately responsive to energy consumption (in contrast to heating and ventilation which vary over longer time periods). Our ultimate goal is to allow PACE horticulture infrastructure to present itself as a "shiftable load" to the electricity grid. This type of demand flexibility management is often deployed in complex, time-critical industrial processes where power consumption schedules can be varied provided that the final product falls within acceptable tolerances. Demand flexing has significant commercial advantages and will be increasingly important as controllable (fossil fuel) energy generation decreases as a proportion of our electricity supply.

Despite the potential advantages of demand flexing for PACE horticulture we still need to determine how crop growth is affected by varied light irradiation. Plants alter their development dependent on prevailing environmental conditions. Varied light regimes consequently produce variation within the crops produced. We can control this 'developmental plasticity' by genetically manipulating the signalling pathways which control plants responses to light. We will assess whether previously generated 'timeless' plants (which we have designed to respond uniformly to light signals) are better able to maintain crop yield, quality, and uniformity when demand flexing is applied.

In this project we have three distinct aims;

1) We need to demonstrate that demand flexing is applicable in PACE horticulture so that we can optimise energy usage whilst maximising crop productivity.

2) We need to understand how demand flexing can be integrated with existing flexible light regimes to maximise crop yield and quality.

3) We need to confirm that our genetically engineered 'timeless' plants have uniform performance during demand flexing so that we can maximise crop productivity and achieve Net Zero goals.

Objectives

We will exploit our understanding of crop photobiology and existing genetic resources to understand how best to apply demand flexing to PACE horticulture.

1) We will assess the growth and biochemical characteristics of crops grown under exemplar demand flexing schemes to demonstrate the utility of this approach.

2) We will assess how demand flexing can be integrated with a varied light regime to maximise crop yield.

3) We will assess the performance of 'timeless' plants in PACE horticulture so that we can maximise crop productivity during the application of demand flexing.

Applications and Benefits

The positioning of PACE horticulture as flexible assets in the evolving smart electricity grid will have commercial benefits for growers and will enhance the viability of the industry. Increased commercial viability of PACE horticulture will allow the distribution of infrastructure alongside sites of renewable energy generation. This distributed production will have societal benefits beyond those conferred by their produce alone. For instance, a distributed placement of smaller scale indoor farms within communities will reduce food mileage and provide job opportunities within these areas, enabling a Just Transition in energy use.