We used Aurora to see if solar is a good fit for Buckingham Palace, where the panels would go, and how much of their energy use the royal family might offset. The results may surprise you\u2026<\/p>\n\n\n\n
\n\n\n\n
In this article:<\/strong><\/h5>\n\n\n\n\n- Estimating the energy load<\/a><\/li>\n\n\n\n
- Modelling the site with Aurora<\/a><\/li>\n\n\n\n
- How many panels fit?<\/a><\/li>\n\n\n\n
- The shading reality<\/a><\/li>\n\n\n\n
- The optimised design<\/a><\/li>\n\n\n\n
- The verdict<\/a><\/li>\n\n\n\n
- What this means for real-world solar design<\/a><\/li>\n\n\n\n
- Frequently asked questions<\/a><\/li>\n<\/ul>\n\n\n\n
\n\n\n\nStep 1: Estimating the Energy Load<\/strong><\/h2>\n\n\n\nBefore we can design a solar system, we need to know the energy load we\u2019re trying to offset. For a building this size, that takes some doing. Let\u2019s go at it a couple different ways.<\/p>\n\n\n\n
The floor-area approach<\/strong> <\/p>\n\n\n\nBuckingham Palace covers more than 77,000 square meters of floor space. That\u2019s 775 rooms across multiple wings, including 19 state rooms, 92 offices, and 188 staff bedrooms. But, Buckingham Palace doesn\u2019t have the energy profile of your typical 1 bedroom flat in the West End, so we can\u2019t just multiply up a typical household\u2019s use. Looking at more typical large historic buildings in the UK, they use roughly 50\u201380 kWh per square meter per year in electricity. <\/p>\n\n\n\n
\n- Low estimate: 77,000 m\u00b2 \u00d7 50 kWh\/m\u00b2 = 3.85M kWh\/year<\/strong><\/li>\n\n\n\n
- Mid estimate: 77,000 m\u00b2 \u00d7 55 kWh\/m\u00b2 = 4.2M kWh\/year<\/strong><\/li>\n<\/ul>\n\n\n\n
That feels a little better. Let\u2019s say it\u2019s somewhere around 4M kWh\/year<\/strong>, and let\u2019s actually cross-check that against the real number.<\/p>\n\n\n\nThe cross-check<\/strong><\/p>\n\n\n\nThe Sovereign Grant Annual Report, the Royal Household’s published financial accounts, records that Buckingham Palace consumed 4.3 million kWh<\/strong> of electricity from the grid annually. The floor-area estimate lands within 7% of the official figure, which is about as good as a methodology check gets.<\/p>\n\n\n\nTo answer your next question, 4.3 million kWh is roughly equivalent to the annual electricity consumption of 1,200 average UK homes<\/strong> (at ~3,500 kWh\/household). It also represents more than 40% of the entire Royal Estate’s electricity usage.<\/p>\n\n\n\nStep 2: Modelling the Site with Aurora<\/strong><\/h2>\n\n\n\nOK, now that we have our target, the next step is to build a 3D model of the site as accurately as possible. This is where the design process can get hairy, and where having the right tools makes a big difference.<\/p>\n\n\n\n
Starting with the aerial image:<\/strong><\/p>\n\n\n\n![\"\"](\"https:\/\/aurorasolar.com\/uk\/wp-content\/uploads\/sites\/4\/2026\/11\/Buckingham-Satellite.jpg\")
<\/figure>\n\n\n\nThe palace presents a classic challenge (well, as much as a 775-room, literal castle can be a \u201cclassic challenge\u201d): a complex, multi-wing roof with chimneys, dormers, flat sections, and pitched sections at a variety of interesting orientations. Pretty safe to say that a rough roof trace could introduce some serious errors in panel fit and shading calculations.<\/p>\n\n\n\n
Bringing in LIDAR:<\/strong><\/p>\n\n\n\n![\"\"](\"https:\/\/aurorasolar.com\/uk\/wp-content\/uploads\/sites\/4\/2026\/11\/Buckingham-LIDAR.jpg\")
<\/figure>\n\n\n\nNever fear, we can use Aurora’s LIDAR integration to pull in elevation data from publicly available LIDAR datasets. in the UK, that means the Environment Agency’s 1m-resolution national LIDAR programme. This converts a flat roof trace into a precisely-pitched 3D model, capturing the actual geometry of each roof plane.<\/p>\n\n\n\n
Drawing the roof with SmartRoof:<\/strong><\/p>\n\n\n\n![\"\"](\"https:\/\/aurorasolar.com\/uk\/wp-content\/uploads\/sites\/4\/2026\/11\/Buckingham-SmartRoof.jpg\")
Screenshot<\/figcaption><\/figure>\n\n\n\nOK, we still have some serious work ahead, so let\u2019s use another tool: SmartRoof. By simply tracing the outline of a roof, SmartRoof will automatically infer the roof structure and fit them to the LIDAR surface. For a building that\u2019s this complex, that can be the difference between hours of manual tracing (again, likely and understandably with errors), and a time-saving model you can trust for shading calculations.<\/p>\n\n\n\n
Mapping the trees:<\/strong><\/p>\n\n\n\n![\"\"](\"https:\/\/aurorasolar.com\/uk\/wp-content\/uploads\/sites\/4\/2026\/11\/Buckingham-Trees.jpg\")
<\/figure>\n\n\n\nOf course, it doesn\u2019t stop there. The gardens contain many beautiful mature trees, several of which are tall enough to cast shade onto the lower roof sections. Let\u2019s go to Aurora’s tree-mapping tool. It places the trees as 3D shading objects, so they are captured in the simulation rather than discovered after installation.<\/p>\n\n\n\n
Now we have a model we can design against. <\/p>\n\n\n\n
Step 3: How Many Panels Actually Fit?<\/strong><\/h2>\n\n\n\nWith the 3D model in hand, we can answer our first question: How many panels can<\/em> we place on the available roof space?<\/p>\n\n\n\n![\"\"](\"https:\/\/aurorasolar.com\/uk\/wp-content\/uploads\/sites\/4\/2026\/11\/Buckingham-Max.jpg\")
<\/figure>\n\n\n\nUsing max fit to place panels across all usable roof space \u2014 every south, east, and west-facing plane with enough clearance \u2014 gives us:<\/p>\n\n\n\nMetric<\/strong><\/td>Value<\/strong><\/td><\/tr>Total panels<\/td> 4,605<\/td><\/tr> System size<\/td> ~1.5 MW<\/td><\/tr> Roof planes used<\/td> Multiple (all orientations)<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\nWow. This would no doubt be one of the largest rooftop solar installations in Central London, or even farther. And on the screen, the numbers look impressive.<\/p>\n\n\n\n
But, this feels a little too good to be true. Let\u2019s go a little deeper to see what actually works.<\/p>\n\n\n\n
Step 4: The Shading Reality<\/strong><\/h2>\n\n\n\nUnfortunately, we know that simply placing a panel on a roof doesn’t mean it will produce enough energy to make it worthwhile. For a literal castle surrounded by trees, chimneys, parapets (yep, that\u2019s right, parapets), and other structures, shading losses will no doubt make some roof sections a no go.<\/p>\n\n\n\n![\"\"](\"https:\/\/aurorasolar.com\/uk\/wp-content\/uploads\/sites\/4\/2026\/11\/Buckingham-SunPath.jpg\")
Screenshot<\/figcaption><\/figure>\n\n\n\nSo, we\u2019ll run Aurora’s shading analysis to get a full annual simulation. It calculates the Total Solar Resource Fraction (TSRF), a combined measure of irradiance availability and shading loss, for every panel.<\/p>\n\n\n\n![\"\"](\"https:\/\/aurorasolar.com\/uk\/wp-content\/uploads\/sites\/4\/2026\/11\/Buckingham-TSRF-1.jpg\")
<\/figure>\n\n\n\n![\"\"](\"https:\/\/aurorasolar.com\/uk\/wp-content\/uploads\/sites\/4\/2026\/11\/Buckingham-TSRF-2.jpg\")
<\/figure>\n\n\n\nAnd the shading map tells a story we sort of expected: Large segments of the roof \u2014 particularly north-facing planes, areas behind chimneys and parapets, and sections close to the tree line \u2014 get a lot less sun. So, installing panels there just doesn\u2019t make sense, for economic and performance reasons. After all, in a grid-connected system with no storage, heavily shaded strings can drag down the performance of adjacent panels through mismatch losses.<\/p>\n\n\n\n
Step 5: The Optimised Design<\/strong><\/h2>\n\n\n\nTo keep things efficient, let\u2019s apply a TSRF threshold of \u226575%. This removes all the panels where shading and irradiance losses are too high. We get a smaller, but far more viable, system.<\/p>\n\n\n\n![\"\"](\"https:\/\/aurorasolar.com\/uk\/wp-content\/uploads\/sites\/4\/2026\/11\/Buckingham-Design-1.jpg\")
<\/figure>\n\n\n\n![\"\"](\"https:\/\/aurorasolar.com\/uk\/wp-content\/uploads\/sites\/4\/2026\/11\/Buckingham-Design-2.jpg\")
<\/figure>\n\n\n\n![\"\"](\"https:\/\/aurorasolar.com\/uk\/wp-content\/uploads\/sites\/4\/2026\/11\/Buckingham-Design-3.jpg\")
<\/figure>\n\n\n\nMetric<\/strong><\/td>Max fill design<\/strong><\/td>Optimised design (TSRF \u226575%)<\/strong><\/td><\/tr>Panels<\/td> 4,605<\/td> ~740<\/td><\/tr> System size<\/td> ~1.5 MW<\/td> ~250 kW<\/td><\/tr> Reduction<\/td> \u2014<\/td> 84% fewer panel
<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\nNow, it\u2019s important to understand that cutting 84% of the panels doesn’t mean the system is 84% less valuable. Every panel is producing near capacity, creating an efficient, economically viable system.<\/p>\n\n\n\n
Step 6: The Verdict<\/strong><\/h2>\n\n\n\nWith the optimised 250 kW system modelled against UK irradiance data for central London (~1,000 kWh\/m\u00b2\/year, pretty standard for northern Europe), here\u2019s what we get:<\/p>\n\n\n\nMetric<\/strong><\/td>Value<\/strong><\/td><\/tr>System size<\/td> ~250 kW<\/td><\/tr> Annual production<\/td> ~206,678 kWh<\/td><\/tr> Annual consumption<\/td> ~4.3M kWh<\/td><\/tr> Offset<\/td> ~5%<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\nThat\u2019s a pretty nice system, until we get to the 5% offset. Woof. Obviously that\u2019s not ideal for any solar install, but we can\u2019t control how much electricity they use or the quirky roof. But, that in itself, is a valid conclusion. Without accurate solar software, we might\u2019ve just tried that 1.5 MW install and nobody would be happy. <\/p>\n\n\n\n![\"\"](\"https:\/\/aurorasolar.com\/uk\/wp-content\/uploads\/sites\/4\/2026\/11\/Buckingham-Summary.jpg\")
<\/figure>\n\n\n\n<\/p>\n\n\n\n
What This Means for Real-World Solar Design<\/strong><\/h2>\n\n\n\nEven with the modest offset, we think this install might be worth the positive PR and money saved anyway. But, we\u2019re unapologetic solar advocates.<\/p>\n\n\n\n
What we can see through this exercise is how important it is to have accurate measurements and projections. Back of the envelope, or designing in your favorite spreadsheet, often doesn\u2019t get you the right answer. Without an accurate 3D model of each roof face, obstruction, and tree, it can be difficult to determine where panels could (or should) fit on the roof. <\/p>\n\n\n\n
A few things Buckingham Palace reveals:<\/p>\n\n\n\n
\n\n\n\n
Step 1: Estimating the Energy Load<\/strong><\/h2>\n\n\n\nBefore we can design a solar system, we need to know the energy load we\u2019re trying to offset. For a building this size, that takes some doing. Let\u2019s go at it a couple different ways.<\/p>\n\n\n\n
The floor-area approach<\/strong> <\/p>\n\n\n\nBuckingham Palace covers more than 77,000 square meters of floor space. That\u2019s 775 rooms across multiple wings, including 19 state rooms, 92 offices, and 188 staff bedrooms. But, Buckingham Palace doesn\u2019t have the energy profile of your typical 1 bedroom flat in the West End, so we can\u2019t just multiply up a typical household\u2019s use. Looking at more typical large historic buildings in the UK, they use roughly 50\u201380 kWh per square meter per year in electricity. <\/p>\n\n\n\n
\n- Low estimate: 77,000 m\u00b2 \u00d7 50 kWh\/m\u00b2 = 3.85M kWh\/year<\/strong><\/li>\n\n\n\n
- Mid estimate: 77,000 m\u00b2 \u00d7 55 kWh\/m\u00b2 = 4.2M kWh\/year<\/strong><\/li>\n<\/ul>\n\n\n\n
That feels a little better. Let\u2019s say it\u2019s somewhere around 4M kWh\/year<\/strong>, and let\u2019s actually cross-check that against the real number.<\/p>\n\n\n\nThe cross-check<\/strong><\/p>\n\n\n\nThe Sovereign Grant Annual Report, the Royal Household’s published financial accounts, records that Buckingham Palace consumed 4.3 million kWh<\/strong> of electricity from the grid annually. The floor-area estimate lands within 7% of the official figure, which is about as good as a methodology check gets.<\/p>\n\n\n\nTo answer your next question, 4.3 million kWh is roughly equivalent to the annual electricity consumption of 1,200 average UK homes<\/strong> (at ~3,500 kWh\/household). It also represents more than 40% of the entire Royal Estate’s electricity usage.<\/p>\n\n\n\nStep 2: Modelling the Site with Aurora<\/strong><\/h2>\n\n\n\nOK, now that we have our target, the next step is to build a 3D model of the site as accurately as possible. This is where the design process can get hairy, and where having the right tools makes a big difference.<\/p>\n\n\n\n
Starting with the aerial image:<\/strong><\/p>\n\n\n\n<\/figure>\n\n\n\nThe palace presents a classic challenge (well, as much as a 775-room, literal castle can be a \u201cclassic challenge\u201d): a complex, multi-wing roof with chimneys, dormers, flat sections, and pitched sections at a variety of interesting orientations. Pretty safe to say that a rough roof trace could introduce some serious errors in panel fit and shading calculations.<\/p>\n\n\n\n
Bringing in LIDAR:<\/strong><\/p>\n\n\n\n<\/figure>\n\n\n\nNever fear, we can use Aurora’s LIDAR integration to pull in elevation data from publicly available LIDAR datasets. in the UK, that means the Environment Agency’s 1m-resolution national LIDAR programme. This converts a flat roof trace into a precisely-pitched 3D model, capturing the actual geometry of each roof plane.<\/p>\n\n\n\n
Drawing the roof with SmartRoof:<\/strong><\/p>\n\n\n\nScreenshot<\/figcaption><\/figure>\n\n\n\nOK, we still have some serious work ahead, so let\u2019s use another tool: SmartRoof. By simply tracing the outline of a roof, SmartRoof will automatically infer the roof structure and fit them to the LIDAR surface. For a building that\u2019s this complex, that can be the difference between hours of manual tracing (again, likely and understandably with errors), and a time-saving model you can trust for shading calculations.<\/p>\n\n\n\n
Mapping the trees:<\/strong><\/p>\n\n\n\n<\/figure>\n\n\n\nOf course, it doesn\u2019t stop there. The gardens contain many beautiful mature trees, several of which are tall enough to cast shade onto the lower roof sections. Let\u2019s go to Aurora’s tree-mapping tool. It places the trees as 3D shading objects, so they are captured in the simulation rather than discovered after installation.<\/p>\n\n\n\n
Now we have a model we can design against. <\/p>\n\n\n\n
Step 3: How Many Panels Actually Fit?<\/strong><\/h2>\n\n\n\nWith the 3D model in hand, we can answer our first question: How many panels can<\/em> we place on the available roof space?<\/p>\n\n\n\n<\/figure>\n\n\n\nUsing max fit to place panels across all usable roof space \u2014 every south, east, and west-facing plane with enough clearance \u2014 gives us:<\/p>\n\n\n\nMetric<\/strong><\/td>Value<\/strong><\/td><\/tr>Total panels<\/td> 4,605<\/td><\/tr> System size<\/td> ~1.5 MW<\/td><\/tr> Roof planes used<\/td> Multiple (all orientations)<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\nWow. This would no doubt be one of the largest rooftop solar installations in Central London, or even farther. And on the screen, the numbers look impressive.<\/p>\n\n\n\n
But, this feels a little too good to be true. Let\u2019s go a little deeper to see what actually works.<\/p>\n\n\n\n
Step 4: The Shading Reality<\/strong><\/h2>\n\n\n\nUnfortunately, we know that simply placing a panel on a roof doesn’t mean it will produce enough energy to make it worthwhile. For a literal castle surrounded by trees, chimneys, parapets (yep, that\u2019s right, parapets), and other structures, shading losses will no doubt make some roof sections a no go.<\/p>\n\n\n\nScreenshot<\/figcaption><\/figure>\n\n\n\nSo, we\u2019ll run Aurora’s shading analysis to get a full annual simulation. It calculates the Total Solar Resource Fraction (TSRF), a combined measure of irradiance availability and shading loss, for every panel.<\/p>\n\n\n\n<\/figure>\n\n\n\n<\/figure>\n\n\n\nAnd the shading map tells a story we sort of expected: Large segments of the roof \u2014 particularly north-facing planes, areas behind chimneys and parapets, and sections close to the tree line \u2014 get a lot less sun. So, installing panels there just doesn\u2019t make sense, for economic and performance reasons. After all, in a grid-connected system with no storage, heavily shaded strings can drag down the performance of adjacent panels through mismatch losses.<\/p>\n\n\n\n
Step 5: The Optimised Design<\/strong><\/h2>\n\n\n\nTo keep things efficient, let\u2019s apply a TSRF threshold of \u226575%. This removes all the panels where shading and irradiance losses are too high. We get a smaller, but far more viable, system.<\/p>\n\n\n\n<\/figure>\n\n\n\n<\/figure>\n\n\n\n<\/figure>\n\n\n\nMetric<\/strong><\/td>Max fill design<\/strong><\/td>Optimised design (TSRF \u226575%)<\/strong><\/td><\/tr>Panels<\/td> 4,605<\/td> ~740<\/td><\/tr> System size<\/td> ~1.5 MW<\/td> ~250 kW<\/td><\/tr> Reduction<\/td> \u2014<\/td> 84% fewer panel
<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\nNow, it\u2019s important to understand that cutting 84% of the panels doesn’t mean the system is 84% less valuable. Every panel is producing near capacity, creating an efficient, economically viable system.<\/p>\n\n\n\n
Step 6: The Verdict<\/strong><\/h2>\n\n\n\nWith the optimised 250 kW system modelled against UK irradiance data for central London (~1,000 kWh\/m\u00b2\/year, pretty standard for northern Europe), here\u2019s what we get:<\/p>\n\n\n\nMetric<\/strong><\/td>Value<\/strong><\/td><\/tr>System size<\/td> ~250 kW<\/td><\/tr> Annual production<\/td> ~206,678 kWh<\/td><\/tr> Annual consumption<\/td> ~4.3M kWh<\/td><\/tr> Offset<\/td> ~5%<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\nThat\u2019s a pretty nice system, until we get to the 5% offset. Woof. Obviously that\u2019s not ideal for any solar install, but we can\u2019t control how much electricity they use or the quirky roof. But, that in itself, is a valid conclusion. Without accurate solar software, we might\u2019ve just tried that 1.5 MW install and nobody would be happy. <\/p>\n\n\n\n<\/figure>\n\n\n\n<\/p>\n\n\n\n
What This Means for Real-World Solar Design<\/strong><\/h2>\n\n\n\nEven with the modest offset, we think this install might be worth the positive PR and money saved anyway. But, we\u2019re unapologetic solar advocates.<\/p>\n\n\n\n
What we can see through this exercise is how important it is to have accurate measurements and projections. Back of the envelope, or designing in your favorite spreadsheet, often doesn\u2019t get you the right answer. Without an accurate 3D model of each roof face, obstruction, and tree, it can be difficult to determine where panels could (or should) fit on the roof. <\/p>\n\n\n\n
A few things Buckingham Palace reveals:<\/p>\n\n\n\n
Buckingham Palace covers more than 77,000 square meters of floor space. That\u2019s 775 rooms across multiple wings, including 19 state rooms, 92 offices, and 188 staff bedrooms. But, Buckingham Palace doesn\u2019t have the energy profile of your typical 1 bedroom flat in the West End, so we can\u2019t just multiply up a typical household\u2019s use. Looking at more typical large historic buildings in the UK, they use roughly 50\u201380 kWh per square meter per year in electricity. <\/p>\n\n\n\n
- \n
- Low estimate: 77,000 m\u00b2 \u00d7 50 kWh\/m\u00b2 = 3.85M kWh\/year<\/strong><\/li>\n\n\n\n
- Mid estimate: 77,000 m\u00b2 \u00d7 55 kWh\/m\u00b2 = 4.2M kWh\/year<\/strong><\/li>\n<\/ul>\n\n\n\n
That feels a little better. Let\u2019s say it\u2019s somewhere around 4M kWh\/year<\/strong>, and let\u2019s actually cross-check that against the real number.<\/p>\n\n\n\n
The cross-check<\/strong><\/p>\n\n\n\n
The Sovereign Grant Annual Report, the Royal Household’s published financial accounts, records that Buckingham Palace consumed 4.3 million kWh<\/strong> of electricity from the grid annually. The floor-area estimate lands within 7% of the official figure, which is about as good as a methodology check gets.<\/p>\n\n\n\n
To answer your next question, 4.3 million kWh is roughly equivalent to the annual electricity consumption of 1,200 average UK homes<\/strong> (at ~3,500 kWh\/household). It also represents more than 40% of the entire Royal Estate’s electricity usage.<\/p>\n\n\n\n
Step 2: Modelling the Site with Aurora<\/strong><\/h2>\n\n\n\n
OK, now that we have our target, the next step is to build a 3D model of the site as accurately as possible. This is where the design process can get hairy, and where having the right tools makes a big difference.<\/p>\n\n\n\n
Starting with the aerial image:<\/strong><\/p>\n\n\n\n
<\/figure>\n\n\n\nThe palace presents a classic challenge (well, as much as a 775-room, literal castle can be a \u201cclassic challenge\u201d): a complex, multi-wing roof with chimneys, dormers, flat sections, and pitched sections at a variety of interesting orientations. Pretty safe to say that a rough roof trace could introduce some serious errors in panel fit and shading calculations.<\/p>\n\n\n\n
Bringing in LIDAR:<\/strong><\/p>\n\n\n\n
<\/figure>\n\n\n\nNever fear, we can use Aurora’s LIDAR integration to pull in elevation data from publicly available LIDAR datasets. in the UK, that means the Environment Agency’s 1m-resolution national LIDAR programme. This converts a flat roof trace into a precisely-pitched 3D model, capturing the actual geometry of each roof plane.<\/p>\n\n\n\n
Drawing the roof with SmartRoof:<\/strong><\/p>\n\n\n\n
Screenshot<\/figcaption><\/figure>\n\n\n\n OK, we still have some serious work ahead, so let\u2019s use another tool: SmartRoof. By simply tracing the outline of a roof, SmartRoof will automatically infer the roof structure and fit them to the LIDAR surface. For a building that\u2019s this complex, that can be the difference between hours of manual tracing (again, likely and understandably with errors), and a time-saving model you can trust for shading calculations.<\/p>\n\n\n\n
Mapping the trees:<\/strong><\/p>\n\n\n\n
<\/figure>\n\n\n\nOf course, it doesn\u2019t stop there. The gardens contain many beautiful mature trees, several of which are tall enough to cast shade onto the lower roof sections. Let\u2019s go to Aurora’s tree-mapping tool. It places the trees as 3D shading objects, so they are captured in the simulation rather than discovered after installation.<\/p>\n\n\n\n
Now we have a model we can design against. <\/p>\n\n\n\n
Step 3: How Many Panels Actually Fit?<\/strong><\/h2>\n\n\n\n
With the 3D model in hand, we can answer our first question: How many panels can<\/em> we place on the available roof space?<\/p>\n\n\n\n
<\/figure>\n\n\n\nUsing max fit to place panels across all usable roof space \u2014 every south, east, and west-facing plane with enough clearance \u2014 gives us:<\/p>\n\n\n\n
Metric<\/strong><\/td> Value<\/strong><\/td><\/tr> Total panels<\/td> 4,605<\/td><\/tr> System size<\/td> ~1.5 MW<\/td><\/tr> Roof planes used<\/td> Multiple (all orientations)<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n Wow. This would no doubt be one of the largest rooftop solar installations in Central London, or even farther. And on the screen, the numbers look impressive.<\/p>\n\n\n\n
But, this feels a little too good to be true. Let\u2019s go a little deeper to see what actually works.<\/p>\n\n\n\n
Step 4: The Shading Reality<\/strong><\/h2>\n\n\n\n
Unfortunately, we know that simply placing a panel on a roof doesn’t mean it will produce enough energy to make it worthwhile. For a literal castle surrounded by trees, chimneys, parapets (yep, that\u2019s right, parapets), and other structures, shading losses will no doubt make some roof sections a no go.<\/p>\n\n\n\n
Screenshot<\/figcaption><\/figure>\n\n\n\n So, we\u2019ll run Aurora’s shading analysis to get a full annual simulation. It calculates the Total Solar Resource Fraction (TSRF), a combined measure of irradiance availability and shading loss, for every panel.<\/p>\n\n\n\n
<\/figure>\n\n\n\n<\/figure>\n\n\n\nAnd the shading map tells a story we sort of expected: Large segments of the roof \u2014 particularly north-facing planes, areas behind chimneys and parapets, and sections close to the tree line \u2014 get a lot less sun. So, installing panels there just doesn\u2019t make sense, for economic and performance reasons. After all, in a grid-connected system with no storage, heavily shaded strings can drag down the performance of adjacent panels through mismatch losses.<\/p>\n\n\n\n
Step 5: The Optimised Design<\/strong><\/h2>\n\n\n\n
To keep things efficient, let\u2019s apply a TSRF threshold of \u226575%. This removes all the panels where shading and irradiance losses are too high. We get a smaller, but far more viable, system.<\/p>\n\n\n\n
<\/figure>\n\n\n\n<\/figure>\n\n\n\n<\/figure>\n\n\n\nMetric<\/strong><\/td> Max fill design<\/strong><\/td> Optimised design (TSRF \u226575%)<\/strong><\/td><\/tr> Panels<\/td> 4,605<\/td> ~740<\/td><\/tr> System size<\/td> ~1.5 MW<\/td> ~250 kW<\/td><\/tr> Reduction<\/td> \u2014<\/td> 84% fewer panel
<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\nNow, it\u2019s important to understand that cutting 84% of the panels doesn’t mean the system is 84% less valuable. Every panel is producing near capacity, creating an efficient, economically viable system.<\/p>\n\n\n\n
Step 6: The Verdict<\/strong><\/h2>\n\n\n\n
With the optimised 250 kW system modelled against UK irradiance data for central London (~1,000 kWh\/m\u00b2\/year, pretty standard for northern Europe), here\u2019s what we get:<\/p>\n\n\n\n
Metric<\/strong><\/td> Value<\/strong><\/td><\/tr> System size<\/td> ~250 kW<\/td><\/tr> Annual production<\/td> ~206,678 kWh<\/td><\/tr> Annual consumption<\/td> ~4.3M kWh<\/td><\/tr> Offset<\/td> ~5%<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n That\u2019s a pretty nice system, until we get to the 5% offset. Woof. Obviously that\u2019s not ideal for any solar install, but we can\u2019t control how much electricity they use or the quirky roof. But, that in itself, is a valid conclusion. Without accurate solar software, we might\u2019ve just tried that 1.5 MW install and nobody would be happy. <\/p>\n\n\n\n
<\/figure>\n\n\n\n<\/p>\n\n\n\n
What This Means for Real-World Solar Design<\/strong><\/h2>\n\n\n\n
Even with the modest offset, we think this install might be worth the positive PR and money saved anyway. But, we\u2019re unapologetic solar advocates.<\/p>\n\n\n\n
What we can see through this exercise is how important it is to have accurate measurements and projections. Back of the envelope, or designing in your favorite spreadsheet, often doesn\u2019t get you the right answer. Without an accurate 3D model of each roof face, obstruction, and tree, it can be difficult to determine where panels could (or should) fit on the roof. <\/p>\n\n\n\n
A few things Buckingham Palace reveals:<\/p>\n\n\n\n
- Mid estimate: 77,000 m\u00b2 \u00d7 55 kWh\/m\u00b2 = 4.2M kWh\/year<\/strong><\/li>\n<\/ul>\n\n\n\n