© FSK TECHNOLOGY RESEARCH 2009
WHY AN EU RENEWABLE ENERGY PLAN NEEDS SOLAR POWER
Background to EU energy issues –
Climate science points to a reduction in carbon emissions of at least 80% by 2050. In practice, this will require the decarbonisation of at least 90% of most types of EU energy supplies. The average energy useage in the EU is currently about 125 kwhr/person/day (IEA). By 2050, it is reasonable to expect efficiency savings and mode alteration to reduce this energy consumption to about 100 kwhr/person/ day, which is equivalent to 4kW continuous mean power consumption per person.
The current population of the EU27 is 500M (Eurostat).
So by 2050, the EU primary energy use will be of the order of
500M+ x 4 kW = 2000+ GW mean
There is insufficient uranium ore to power a nuclear powered future, even if that were desirable, as 1000 GW of conventional nuclear power can only be fuelled for about 15 years with the currently known sources of ore. CCS is an unknown quantity and it is unlikely that the massive scale of CO2 sequestration required could be achieved on this scale, even if it were desirable. So huge renewable energy sources are essential.
To power this by wind at a generous 30% capacity factor will require 6,600 GWp+
which means > 2 M turbines (using 3 MW average sized units )
At an optimistic 2 W/m2 mean power / unit area this equates to 10^12 m2 of land area : or 1M km2 , equivalent to a square 1000 x 1000 km on a side
The population to be served in the greater EU+ with North Africa etc will be well over 1bn, so the land area required is prohibitive. There is no prospect that the EU will accept a sizeable proportion of its primary energy being supplied by Russia, which is likely to need its own renewable resources in any case.
Desert sourced CSP ( PV) solar power has two major advantages over wind
- The energy generation density is an order of magnitude greater at 15 (30) W per square metre so the land usage is an order lower, and quite manageable. 500GW CSP needs the land in a square about 150 x 150 km
- CSP with storage is dispatchable and can provide the essential backup continuity for a north european wind/ renewable grid
Thus (in mean GW units)
- Nuclear is unlikely to supply more than 200GW (France already has 70GW)
- CCS coal/gas/oil is unlikely to supply more than 500GW
- Wind is unlikely to provide more than 500GW
- Solar is likely to be the largest single contributor at 500GW+
- Other distributed renewables will add 300GW
A realistic renewable energy scenario is one where there is a rapid wind build-up in northern europe, which will soon exhaust all the low cost land based regions, then higher cost offshore wind will be exploited. This will create an increasing need for wind intermittancy grid balancing to stabilise the high penetration of variable wind power supplied to the grid. As dispatchable solar power has higher value to the grid than wind power, solar power will rapidly increase in overall capacity till it rises above wind and becomes the predominant renewable power source.
The current relatively high cost of solar power has been used as a reason for precluding it from large scale use. But industrial scale CSP and PV are only in gestation. Recent indications from the US are that industrialising the manufacture of solar fields and other components, with cost as the driver, dramatically reduces the levelised cost of the electricity produced, so large scale CSP with storage will produce electricity at comparable prices to wind. PV solar panels (CdTe based) already cost < 1$ / Watt and PV panel farms will be economically deployed on a very large (GW) scale. Higher efficiency concentrated PV panels will be deployed on buildings where cost is a less important factor.
There are several key requirements for the creation of a credible renewable dominated energy future for the EU-
- ENERGY EFFICIENCY
The highest priority for a renewable energy future is to stabilise primary energy demand by efficiency measures, with active demand control and thermodynamic gain making major contributions
- SMART GRID
A Smart grid will distribute centrally generated large scale and smaller scale locally generated power and balance demand with supply from consumption to generation. Smart interconnection involves new smart appliances at the micro scale all the way up to Super- grid interconnections
- RENEWABLE MIX
All the available renewables will be needed to create a renewable energy future: wind, hydro, solar thermal, CSP and PV, etc. The final mix will be seasonably variable and have a considerable supply margin
This is needed both for grid stabilisation and to accept the large peaks in supply that are inherent in renewable generation. Primary storage of generated electricity by hydro and car batteries can be supplemented by some secondary heat storage.
- THERMODYNAMIC GAIN
Using heat pumps to convert excess peak electricity supplies into low grade heat has the potential to usefully convert and multiply generation peaks for building heating.