'..... it would break the laws of physics if emissions and fuel use didn’t go down when wind was contributing.' - American Wind Energy Association
Is wind energy, endorsed by co-sponsors BirdLife South Africa & Investec, a blast of hot air?
From the BLSA site [BirdLife South Africa] the following -
'The need for cleaner energy has resulted in a burgeoning renewable energy industry in South Africa. At BirdLife South Africa we acknowledge the predicted shortfall of evergy [(sic) - presumably 'energy'] supply versus demand. We also recognise the need to include more renewable energy in our energy mix if the threat of climate change is to be reduced. BirdLife South Africa therefore supports the responsible development of a renewable energy industry in South Africa.'
Good intentions, clearly, but a little naive. Let's cut to it. We know birds are killed by turbines. In fact, a median estimate suggests some 300 000+ birds are killed in the US each year [Smithsonianmag.com]. Seabirds are at greater risk! [BirdLife International] To conclude before we begin and without being disparaging, the co-sponsored outdoor advert 'without impact' is misleading, if not high-grade BS. A claim of 'with minimal impact' is more accurate but let's not get into the semantics of language.
BLSA makes reference to the burgeoning renewable energy industry & this is key. The emphasis on burgeoning is mine.
What is wind energy?
What are the purported benefits of wind energy? - ( per the Jeffreys Bay Wind Farm )
- Wind is a clean, renewable energy source. There are many environmental benefits of wind energy, including:
- Water saving – wind energy does not consume water during the energy generation process, it also helps preserve scarce water resources.
- Reduced carbon emissions – one megawatt of wind energy equates to 2600 fewer tons of carbon emissions when compared to coal-fired energy generation.
- Wind energy generation emits zero air or water pollution.
- Annual emissions avoided | 420 000 tonnesCO2
- Project lifetime CO2 emissions avoided | 8 400 000 tonnes
- Water savings | 590 000 000 litres per year
South Africa's Eskom [Eskom - Renewable_Energy] reached full capacity [annual 233000 MWh or approx. 95000 homes] at its own Sere Farm; a wind farm near Vredendal in the Western Cape. As an aside, Eskom's published map of Sere uncannily resembles BirdLife's own published map of the nearby Olifant's River Estuary [Olifants-river-estuary], an IBA [Important Bird Area].
Other local wind projects, including the wind facility near Darling in the Western Cape, claim the same benefits.
That's all good & well if you take the data at face value. Unavoidably, bias is inherent in most projects - good & bad.
Forbes - wind-energy-carbon published an article on a real-world study by Bentek Energy [now Platts], an energy analytics firm. The study concluded that wind-energy's carbon-reduction figures were, in many cases, grossly overstated and as a consequence, too expensive to be commercially scaled. Proponents of renewable energy refute their conclusions [Quora]. In context the Bentek study was sponsored by the Independent Petroleum Association of Mountain States... Debated inaccuracies notwithstanding, Bentek concentrated on the emissions of coal plants ie: when these facilities are continually cycled as backup for the variability of wind production. This is important.
The wind industry's claim on emissions-savings relies on two assumptions:
- The reduction in production from coal-fired plants = a proportionate drop in emissions.
- The wind's vagaries does not impact coal-fired facilities.
Both assumptions are false.
Base-load energy production [**I'll get to this in a minute] ie: coal & nuclear, are designed to be efficient at optimal levels of production. Emissions increase as production & efficiencies decline. Wind production fluctuates with wind speed. To balance the grid other generators work harder. This increases emissions to the point where savings from wind may, in fact, be negative.
**Base-load production is the high-efficiency production of energy, at a constant rate and usually at low cost. Base-load plants don't usually adjust output to comply with increased consumer demand. Peaks or spikes in demand are often provided for by smaller, less efficient peaking power plants eg: gas & wind. [Caveat - renewable energy sources are, however, sometimes incorporated into the base-load production.]
Jeffrey's Bay Wind Farm claims a saving of 8 400 000 tonnes of CO2 over the project's life-cycle. Most often these kinds of figures are calculated on displacement ie: where each wind kWh eliminates the emissions from a coal-fired plant generating the same kWh BUT this almost always ignores the CO2 emissions that are created [backup] to compensate for variance in wind production.
The problem, generally, is a lack of production control. This leads to the prevalence of / need for backup plants - almost always running at lower efficiencies & usually at higher emissions.
Eskom confirmed, very recently, that the utility was reviewing the role of renewable energy [Eskom - review] for the same reasons I've outlined above. It's an interesting take & the criticism of Eskom's position has been fierce. Notwithstanding, intuition & reality are not always interchangeable.
Returning to BLSA's commitment to mitigating bird mortality - we know collisions kill birds. That fact has been widely reported by BirdLife International themselves. An improperly placed turbine can & does have a disproportionate impact on birds. Sensitive habitat destruction is also a valid concern. Understanding the impact on the birds themselves and on the habitat as a whole, I would assume, is key to BirdLife's monitoring process. In addition, newer turbines are purported to have less direct impact on flying birds & that's good news of course.
What is not as broadly reported is the negative effect of turbines on bats. In addition to collisions, bats suffer fatalities without coming into contact with the blade itself. At close quarters the rapid change of air pressure results in barotrauma or pulmonary edema [oedema]. Estimates as high as 15 bats per turbine are quoted. There are 314000 [approx.] wind turbines around the globe [No. of wind turbines]
I concede the merits of progress & the energy demands of an unchecked population. I understand profit and the incentive to innovate. What you may not know, however, is that the Jeffrey's Bay Wind Farm is owned by a consortium which includes local financial investment companies. That's fair enough of course. If opportunity doesn't knock, build a turbine...What I don't like is the disingenuous claim that wind proportionately reduces carbon emissions and let's be honest; that's the sales pitch.
As for our two co-sponsors & their endorsement of wind energy, two things come to mind. Firstly, I'm not convinced that Bird'Life' South Africa has the mandate to publicly celebrate a product that in itself is factually indefensible however well it's done. Secondly, whilst Investec's motivations are an internal matter, I assume their CSR models are broadly relevant. Nobody likes a spoilsport.
As for me, I enjoy my coastlines & mountains free of whirly-junk. What's wrong with that?
