EME 810
Solar Resource Assessment and Economics

10.3. Scale of Solar and Ecosystem Services

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Reading Assignment

Now we are going to tie our focus on scale to ecological impact. This reading is complementary to the concept of solar energy. Consider that large scale solar is called a "solar farm" or community scale solar can be termed "solar gardens." Large scale farming leads to large scale land use changes, and may undermine environmental resilience and existing ecosystems services.

Scale of Solar: Now and in the Future

We keep hearing about exponential growth of the solar industry, and larger and larger SECS projects are being rolled out each year. Solar consumes a lot of land, so here we especially focus on the impacts that come with major land use changes. Consider how the land use of these solar projects is linked to the observed ecological disruptions.

Gujarat Solar Park in Gujarat, India:

  • Only began installing in 2011, and nearly 1,100 MWp of PV completed as of 2016.
  • Chankara Solar Park consumes the largest area: 4,900 acres (19.8 km2 or 7.7 mi2); eventually host 500 MW of PV (an average of 9 acres per MW installed, or 25 MW for every 1 km2).
  • This is very, very fast development of power.
  • Neighboring state of Rajasthan, India is planning for 4000 MWp of solar power in the near future.

Ivanpah Solar Power Facility:

  • CSP power tower systems installed in California/Nevada border of the Mojave desert.
  • Unit 1 of 3 was connected in September of 2013.
  • Three solar thermal power stations will consume 4,000 acres (16 km2 or 6.25 mi2) to host 392 MW of power (an average of 24.5 MW per km2).
  • The process was relatively rapid (over the course of 3-5 years), but the CSP plants take longer to install than PV (however, PV does not have evening power storage).
  • Disturbance of the land in the northeastern Mojave Desert (the Ivanpah Valley) was significant to a threatened species of desert tortoise. This lead to a relocation of tortoises by the developer, BrightSource Energy, Inc.
  • The Solar Energy Industries Association describes the Department of the Interior's process associated with the large land permitting process.

These very large solar projects (4,000-5,000 acre scale), started around 2012, are now considered "medium scale”, given the doubling time of PV capacity. There are now Gigawatt scale solar farms in development, with one near Tibet at Longyangxia Dam Solar Park at 850 MW scale (see satellite images from NASA). So the expected ecological impacts will be even more dramatic and may result in not only local, but regional and global consequences. 

Furthermore, the direct land use impacts (such as clearing or changing the land for solar installation) is only a trigger for a larger scale land impact. The Dust Bowl of the USA in the 1930s was initiated by the land use changes of only about 1000 acres in marginal lands, but eventually affected 100 million acres (400 thousand km2). System causal connection and feedbacks within natural ecosystems propagate the initial disturbance to a greater territory and over a greater period of time. 

Recognizing the challenge of cultivating marginal arid land, the United States government expanded on the 160 acres offered under the Homestead Act—granting 640 acres to homesteaders in western Nebraska under the Kinkaid Act (1904) and 320 elsewhere in the Great Plains under the Enlarged Homestead Act (1909).

-Dust Bowl (Wikipedia entry, accessed Nov. 15, 2013)

Ecosystem Services

Significant land areas are being designated for solar projects, including both natural and partially developed. However, the solar development does not have to be detrimental to the health and values of local environment. As well as providing low carbon energy, solar farms can also provide important benefits for biodiversity and ecosystem services. Furthermore, land use change for solar installation presents an opportunity to address the urgent challenges of mitigating ecosystem degradation. In other words, degrading lands can be brought back to health.

However, given the high rate of solar industry development, it is important time now when we need to determine the best ways to design and manage utility scale solar plants. In fact, many solar projects are built on low-grade or otherwise intensively managed agricultural land and may create an opportunity to enhance biodiversity and return the fields to a natural state.

Let us the review the main types of ecosystem services we are talking about here.

Table 10.1. Types and Examples of Ecosystem Services  

Provisioning

Things that we get from the ecosystem: food, water, fresh air, wood, medicines, and other natural resources that fulfill our primary needs

Regulating

Processes in the environment that regulate climate, water cycling and purification, waste degradation, pollination for crops, soil erosion control, pest control, etc.

Cultural

Non-material aesthetic and recreational values we get from being in the nature: e.g. views, hiking trails, fishing lakes, national parks, etc. These will support our emotional well-being and mental health

Supporting

Resources that support all the above services: habitat, flora and fauna, biodiversity, soil.

There are sometimes no distinct boundaries between these types, as the same resource may be considered within several categories. For example, trees or soil can be both part of supporting system and provisioning products. Or another example is storing carbon in biomass can be both regulating (carbon sequestration) and resource generating or provisioning (fossil fuel).

At the stage of solar project design, we may want to take a close look at the ecosystem services existing in the target area and assess their environmental significance for the local community. Next, we may want to plan measures and design features that either have minimal impact on those services, enhance them, and add additional value. At the same time, we may want to avoid the actions or design features that are detrimental.

Try This! SPIES Tool.

A Group of researchers at the Universities of Lancaster and York (UK) developed an online tool – “Solar Park Impacts on Ecosystem Services" (SPIES) – that helps practitioners make informed decisions on solar design and environmental management. This tool is evidence-based, so all the impacts and strength of the impacts associated with different projects activities on site are researched and referenced. SPIES compiles 457 peer-reviewed academic articles collected via a systematic review of relevant issues.

The interactive interface allows users to arrange scientific evidence by ‘ecosystem service’ and to generate a list of management interventions that will affect the achievement of a desired environmental outcome.

The SPIES tool can be used for planning applications by showing how solar projects can contribute to the environmental and biodiversity targets, if managed properly. The options presented by SPIES can help developers decide which ecosystem enhancements will be the most appropriate at the particular locale. This tool can also be useful to local authorities and policy makers who are required to consider environmental benefits and risk and approving project proposals.

Go to the SPIES website: https://www.lancaster.ac.uk/spies/

Scroll down to the bottom and click to download the SPIES tool – you will receive the login information for using the database. Feel free to check out other supporting resources.

Hope you find it useful in your own development!