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 #### Smart Infrastructure: Road sensors
 
 - Disruptive vs Non-disruptive:
-    - ![sensors](./assets/2-sensors.png)
+    - ![sensors](./assets/2-sensors.webp)
 
 #### Smart Vehicles: Vehicle mounted sensors
 
diff --git a/3-smart-grid.md b/3-smart-grid.md
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+# Smart grid
+
+## Not smart grid
+
+- Electric grid, production, delivery and consumption has to occur
+  instantaneously and in perfect balance
+- Reason for not smart:
+    - Frequency matches generation and demand
+    - Voltage is generator and transformer
+    - Current is the upper limit of devices and have to provide spare capacity
+
+## Smart grid
+
+- Features:
+    - Cost efficiency
+    - Economically efficient, sustainable
+    - Quality
+    - Security
+    - Safety
+- How to
+    - Integrate the power infrastructure with Information and Communication
+      Infrastructure
+- Problems present:
+    - Energy Security
+    - Energy Sustainability
+    - Energy equity
+
+## Reason
+
+- The UK Government pledge
+    - Reduce carbon emission by 68% by 2030
+    - more , 2035
+    - net zero by 2050
+- Renewable with the traditional grid: power flow is less predictable
+- Renewable with changing landscape: user demand is more challenging to predict
+- Just In Time Delivery
+    - Dealing with excessive energy
+        - Store
+        - Sell
+        - Run power station
+        - Problem: Excess power may damage device or parts of grid
+    - Not enough energy
+        - Use stored energy
+        - Hydro power
+        - Buy
+        - Problem: risk of black out
+- This means we should use smart grid:
+    - ![smart grid diagram](./assets/3-smart-grid-diagram.webp)
+    - ![another diagram](./assets/3-smart-grid-diagram-2.webp)
+
+## Implementation
+
+### Optimizing the electric grid
+
+- Continuous: Accurate forecast of demand and production to increase cost
+  efficiency, and resilience of electricity provision
+- Predictive: Informed planning of renewable energy and storage to reach net
+  zero
+- Integration and collaboration: integrate with other infrastructures for
+  efficiency and collaborative intelligence
+
+### Big data and smart grid:
+
+- Sources:
+    - ![smart grid big data sources](./assets/3-smart-grid-big-data-sources.webp)
+- Characteristics of big data:
+    - Volume: Amount of data:
+        - Likely terabytes in size
+        - Stores transactions
+        - In form of stream or batch
+    - Variety: Lots of data types:
+        - Structured or unstructured
+        - Multi-factor, and probabilistic
+    - Velocity: Speed of data flow:
+        - Real time
+        - Near real time
+        - In stream or batch
+    - Value: Extracting insights
+        - For business
+        - For revenue streams
+        - Has operational value
+    - Uncertain: Data uncertainty
+        - Authenticity on data
+        - Origin of data
+        - Availability of data
+        - Accountability
+- Analytics: the more sophistication, the more value.
+    - Hindsight: descriptive of what happened
+    - Insight: diagnostic of current situation
+    - Foresight: Prediction, and perspective
+    - ![analytics diagram](./assets/3-smart-grid-analytics.webp)
+- Example:
+    - ![Example](./assets/3-analytics-examples.webp)
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